BRITISH MICROMOUNTSOCIETYNewsletter No.17 June 1986

5TH BRITISH MICROMOUNT SYMPOSIUM - 27/28 SEPT 1986

CHAIRMAN

Roy Starkey 29 Painswick Close, Oakenshaw, Redditch,Worcs 1398 7XU

SECRETARY Elsie Hansford 46 Wydeville Manor Road, Grove Park,London SE12 OEW

MEMBERSHIP SECRETARY/TREASURER Neil Hubbard 122 Cordery Road, Evington, Leicester LE5

60F

YOU WILL FIND ENCLOSED WITH THIS NEWSLETTERAN APPLICATION FORM FOR THE 5TH SYMPOSIUM TOBE HELD AT LEICESTER UNIVERSITY ON 27/28SEPTEMBER 1986.

PLEASE COMPLETE WITHOUT DELAY AND RETURNTO MIKE ROTHWELL SO THAT ORGANISATIONALDETAILS CAN BE FINALISED.

The 6th British Mineral and Gem show held at the Holiday Inn, Swiss Cottage on 15/16March was again a great success and many members met up and enjoyed the ragchew as wellas the minerals. There was great interest in the BMS display and once again the Society wasawarded the Roger Harker Shield for the best club or society display. It presented a livelyperspective of our activities and we are grateful to those who put it together and mannedthe stand throughout the show.

The Society has established a prize fund in the Department of Geology at LeicesterUniversity In recognition of the kindness shown in allowing us to use their facilities. Theprize will be awarded annually to the best practical project submitted in the second yearundergraduate mineralogy course. The prize will be awarded for the first tune this year.

ANNUAL GENERAL MEETING

Notice is hereby given that the 1986 Annual General Meeting of the Society will be held atLeicester University, Leicester on Sunday 28 September at 9.30am during the Symposiumweekend.

It is stressed that every paid up member is entitled to attend the AGM but other weekendactivities are only open to those who enrol for the Symposium. A form for the election ofofficers is enclosed, please return your nomination form, together with any proposals oramendments to the Constitution, or any other matters you wish to place before the AGM tome in writing by Saturday, September 6, 1986.

E HANSFORDSecretary

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OBITUARY - Norman F King

It is with deep regret that we announce the death of Norman King on 17 April 1986. Afterattending the last Symposium at Leicester University he was admitted to hospital and for awhile appeared to be responding to medical treatment. In addition to his strong interest inmicro-minerals Norman was an enthusiastic amateur palaeontologist, curating a largecollection of personally collected sharks teeth and other fossils from Southern England.Meticulous and painstaking in everything he did, Normal also found time to build anextensive stamp collection, and to participate in the recovery of coins of archaeologicalinterest from the South Hampshire area using a metal detector as part of a local group.Whilst perhaps happiest when immersing himself in his individual persuits, Normantransmitted his cheerful enthusiasm to all who met him, and his willingness to listen toothers was a quality many of us respected. The Society will be the poorer without him andwe offer our sincere condolences to his wife Shirley and the family.

Roy Starkey

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ANNUAL FIELD TRIPS - MAY 1986

North WalesDave Middleton

The North Wales meeting started with an irritating disappointment in that permission fromPenmaenmawr quarry was withdrawn on the previous Thursday because "the ,person whodeals with this sort of thing was away ill". So the party moved off to the Great Orme atLlandudno to do a fair amount of collecting between prolonged and heavy showers. Within afew first minutes on the dumps, Peter Wallace found a good specimen of azurite - an inchlong, quarter of an inch wide containing well-crystallised micro azurite associated withmalachite. This raised everyone's hopes but I believe no other crystallised azurite was foundby anyone else. No one was disappointed however, everyone collected sharp chalcopyritecrystals, malachite, calcite and dolomite. The party met at the Plea Gwyn Hotel, PentreFelin, for a meal and social gathering. This was very pleasant even allowing for a somewhatnoisy wedding party to which we were attached.

On Sunday the party went to the classic locality of Prenteg. Within a short time LarryChick had found a brookite crystal - reddish brown 1/4" x 3/4" x 1/64". Other membersfound odd crystals of both brookite and anatase - unfortunately the brookite crystals wereusually broken. A search was made across the hillside but there appears to be no potentialoutside the familiar area itself. Neil Hubbard found a superb quartz crystal (2" x 1" x 1")with a brookite crystal half included within it. In the afternoon, the party moved on to theManod Granite quarry, Blaenau Ffestiniog. Most members found small specimens of anataseand more rarely, brookite. Late in the day Michael Jackson opened up a two foot long vuglined with clear quartz crystals to two inches. Some fragments of brookite were seen onthese specimens as they were collected. After cleaning in the evening and examinationunder the microscope, micro anatase was also found to be present. Very heavy showersmade collecting difficult at times but even then, a small sturdy band de linedto takeshelter.

There was no formal programme for Monday but some members returned to Manod quarry,some went gold panning near Ganllwyd (728246) and others went over the Berwyns toLiangynog. The weather was much better, and members left Wales with a better impressionof its scenery and minerals hopefully to a pleasant journey home.

South West Scotland

1986 Micromount Field Trip to the MetalliferousMines of S W Scotland

Jean Spence

9.30am on Saturday 3rd May saw the party assembling at the Creetown tiern-ROck Museum.We were given a friendly welcome and found that there were many splendid rocks and

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minerals to browse over in this comprehensive collection. Later we all drifted into the cafefor coffee, scones and roll call. Bev called us to order and gave us the itinerary for the day.

The first location was the working Creetown quarry. The manager was very loquacious,explaining the stratigraphy and history of the quarry. The more able amongst us ascended tothe top bench where a mineralised fault could be seen. Kemp Meikle eventually locatedsome Azurite crystals and a few of the party returned to the site later in the day. Alas, theweather pattern for the weekend was established, the rains came down and we all fled to thecars.

We moved on to the Blackcraig Mine tips for lunch. Much of the three to four mile stretchof dump has been removed (the best bits). At the second spot we visited there was a greatdeal of interest in a specimen of "orange balls" until it was realised that we'd all got some inthe specimen we had collected, identification later.

The final site of the day was the Talnotry Arsenic and Nickel Mine dumps. This site ishidden deep in the forest, up a small hidden valley. It really defies discovery. The skygradually darkened and mineral collecting was getting very difficult as the light went. Arumble of thunder, flashes of lightning and then the heavens really opened. We all fled upthe tip to a cave conveniently sited at the top. On the way up I spotted a rock with a palegreen coating on it. Grabbing it I climbed on up into the cave. The rock proved to be theonly sizeable specimen found that day of niccolite and annabergite. The rock was splitasunder into many parts for all to share so, when the rain ceased we all left having each gota 'location specimen'.

The day culminated in an excellent meal at a get together at the Laird's Inn at theCassencarrie Caravan Park.

Sunday dawned bright and clear. With spirits high we all met at the rather boggy caravanpark and set off for the Lauchentyre and King's Laggan Mine dumps. The road to the minesran through some scenic countryside. It got narrower and rougher and finally we slithered toa halt in an odorously muddy farm yard. While attempting to turn into the yard MikeRothwell's car stuck in the mud, his passengers leapt out to do their bit and put theirshoulders to the front. The wheels spun and the mud flew. As Mike Leppington remarked onviewing the drippingly-coated Richard Bell, "Is this the original Spotted Dick?" A sparklingclean Richard later appeared after an encounter with some very cold water from thefarmyard tap and a sponge (donated by the farmer).

The party then split in two, half went to the Lauchentyre tips after 11" wulfenite crystals.Perhaps long ago there was, but all we found was traces of malachite and chalcopyrite. Sowe rejoined the party across the road at King's Laggan Mine. This meant traversing an evenmore mal-odorous and muddy cow track up to the little cut where we had to stand in thestream and search. Liz Yates found a very nice rock full of beautiful chrysocolla, plushmalachite and other copper secondaries. Mike Leppington was pleased with his specimen ofclear barytes crystals with malachite.

The afternoon location and lunch spot was the Pibble Mine dumps, so we headed up the tracktowards the main road. It just wasn't Richard's day. Volunteering to open and close thegates he leapt on to one to swing it. Unfortunately the gate stopped and Richard didn't thusproviding his chauffeur Mike Rothwell (who was feeling very low having been attacked by abug in Japan) with his second guffaw of the day.

The Pibble Mine dumps were away up a hillside. The track petered out in yet anothermorass of cowdung and mud, the farmer having put his feeding trough next to the enginehouse. We nearly lost Doug Morgan who sank his wellie tops in the glutinous stuff. It wasquite hilarious as most of us became embedded and in danger of losing our wellies before wegained safer ground. The tips are quite large and much malachite is evident, nice specimensof linarite, cerussite and aragonite were found and hopefully someone will have erythrite,caledonite and other copper secondaries. An edit was found and Mike Rothwell, MikeLeppington, David Green and Richard Bell returned at the end of the afternoon and ventured

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In only to be met by a fall damming the edit. They believed that had they gone in earlierthey could have released the water enabling them to go in further.

The Laird's Inn was again our meeting spot for the exchange of dates, trips, information anddiscussing the next day's activities.

Monday morning was very wet and dull. One half of the party had decided to visit theErythrite vein at Needle's Eye on the coast. David Green had already been there on tneFriday and collected some nice crystalline specimens. The rest of us went to Wanlockheadover the tops. The weather gradually improved as the slag tip got smaller. We set off forhome in the now accustomed downpour accompanied by the statutory lightning and thunder.Undaunted, we had all had a cracking good weekend, thoroughly enjoyed by all and we giveour sincere thanks to Bev Yates for his affable and efficient leadership all the weekend.

When you have found time to clean up your specimens and examine them, please submit liststo the Newsletter Editor.

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NATIONAL REFERENCE COLLECTION Max Wirth

Requests are now coming in for specimens from the collection and it is gratifying to knowthat people will be making use of it. I am still trying various packaging methods to avoiddamage and excessive weight. Many specimens are arriving in not quite the pristinecondition I would like and it should be the responsibility of the donor to wash specimens(unless they are water-soluble) and dry them to enhance their appearance. The specimenshould be wrapped in clean tissue, preferably unmounted but with a label using as littlesticky tape as possible.

The number of specimens is growing quite rapidly and it is probably time to try and includemore information. May I remind donors that the grid reference consists of two prefixedletters followed by eastings (read from top or bottom margin of map) and northings (readfrom left or right margin). Given in the wrong order they can be very confusing as I do nothave maps for the whole country. Please also check the spelling of the mineral name andlocation. The National Reference Collection is now on computer, listing the mineral, it'snumber, the site by name, the grid reference and the donor. This makes printing lists mucheasier and it would be possible to enter more information. It would be useful if donors wouldgive any relevant references from scientific literature or from magazines, on the back ofthe index slip. The latest list No. 10 includes up to four comments for each specimen,comments which may be useful in choosing which specimens to borrow. The list given belowshows the comments by number, suggested so far and the Hon. Curator would appreciatefurther suggestions:-

1. BLANK2. Very rare3. Very small4. Small site5. Pegmatite6. Several species7. Slag minerals8.9. X-ray

10.

12.13.14.15.16.17.18.

Optical propertiesChemical propertiesPhotogenicRock mineralUndergroundGood crystalsBroken crystalsOther habit

All correspondence in connection with the National Reference Collection to Max WirthParley Hill, Cuirass, Fife KY12 8.3D.

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NEW FINDS

Lettsomite Cu4Al2(SO4) (01-1)12' 2H20

David P. Clough

from the Penberthy Croft Mine, St Hilary, Cornwall.

Occurs as individual bright blue spheres and groups of acicular crystals on platy greencrystals of brochantite, in a cavity in limonitic matrix. The occurence of this species hasbeen confirmed by the Department of Mineralogy at the British Museum (Natural History),who state that although "lettsomite" is usually regarded as a synonym of "cyanotrichite" ithas an easily distinguishable X-ray powder pattern. However, no further work appears tohave been done to resolve the differences.

Paralaurionite Pb(OH)C1 David Green

from the Meadowfoot smelter, Wanlockhead.

Occurs as transparent flexible, lath-like crystals often showing a well-developed cleavageparallel to the long axis. Single crystals may have maximum dimensions of 1mm but areextremely thin. Identified by X-ray diffraction.

Slag Minerals from Wanlockhead Max Wirth

Apart from the now famous eiyite, I have had positive identification of the followingminerals:-

Lanarkite as hemispherical snow-white sprays of needles (not plates) identified by X-ray diffraction at the Royal Scottish Museum.

Malachite as green pustules effervescing in acid but not otherwise characterised.

Aurichalcite as generally flat sprays of blades with typical pale-blue appearance andcharacterised by optical properties.

Langite as pseudo-hexagonal trillings, identified by optical properties.

Linarite as blue blades identified by optical properties.

Most minerals will probably be of the sulphate types and the carbonates are probablytertiary in this sense. Barytes and brochantite should be there!

1985 Field Trip Minerals Max Wirth

A specimen I picked up at the Prince of Wales site looked at first glance like haematite. Itturned out to be blue anatase, not In octahedra but with square edges rather like a galenacleavage. From the Meldon aplite (lower field) I found a piece containing very small brownplates (smokey quartz colour) standing out like barytes but uniaxial negative and tetragonal.Can anyone tell me what they are?

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DYFNGWM MINE Steve Rust

I set out below the possible paragenises of minerals from Dyfngwm mine, near Staylittle,Penegoes, Powys, Wales which was described in Newsletters 15 and 16:-

PeOxidesCerussiteMalachiteLinariteSmithsoniteHydrosinciteZn(OH)2

LangiteAnglesiteDevellinePoenjakiteBrochantiteWroemolfelteCaledonite6Zn(0102ZnSO4 .41120

Leadhillite

IMO

aTo0

2(PbCu4 (304 )2 (011) .3H20

Some minerals may and do overlap in their formation. Overall it appears that the Zn(OH)2minerals postdate the carbonate-based minerals while pre-dating the sulphate-basedminerals, and this must have some bearing on their formation. This does not, however,explain why the later acidic waters have not dissolved the Zn(OH) 2 .

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GOLDSPEAR

A sophisticated metal detector especially developed for gold-seeking has been developed bya Swedish mining engineer called Lars Guldstrom. After thorough testing on sitesthroughout the world it is now being marketed as the Goldspear and was on show at therecent London Gem and Mineral Exhibition. It comprises a four feet long special alloy spearwhich can be pushed into a river bed, beach or other ground with sensing devices to detectblack sand (which registers a crackling sound) and gold (which registers as a bleep). Eachdetected grain results in one bleep and the manufacturers claim that it will signal gold downto 300 mesh at a concentration of only one gram per ton of material. The price of thegoldspear is £385.25. Enquiries to Mrs Norma Bingham, 30 Thornton Avenue, Macclesfield,Cheshire (telephone: 0625 21108).

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BRANCH NEWS

Northern Branch

Jean Spence

The 12 April meeting, attended by 13 members and friends, was devoted mainly to slidepresentations illustrating the variety of forms and colours of pyromorphite from theCaldbeck Fells. Peter Briscoe and Max Freler of the Doncaster Mines Research Groupshowed specimens collected at eight exposures along the Great South Lode of Roughtengill.The wealth of this area had been built on this NE-SW running lode which had been workedbefore Elizabethan times until the end of the 19th century. Starting at the NE end, thepyromorphite from Mexico mine, which was between Blea Gill and Clint's Gill, was mainlyorange-green prismatic crystals on quartz, with some acicular yellow crystals, sometimesmanganese-stained. There were also platelet crystals showing colour zoning, and melonshaped crystals. Locations near Blea Gill had provided museum-quality specimens -botryoidal and prismatic crystals, sometimes transparent and gemmy, yet overlookedfrequently because they were covered in clay. Below Iron Crag acicular crystals, pale-greento white had been found. Some of the crystals were transparent and associated withbarytes. Similar material was common at Roughtengill. All the mineral slides had beentaken with bellows extension and were superb quality.

Michael Cooper then showed a dazzling selection of slides of Caldbeck Fell minerals fromthe best collections in the country, including the British Museum, Oxford University, RussellCollection and private collections. There were pyromorphite/campylite combinations, andspectacular combinations of emerald green, pale green and brown crystals on a specimenfrom Driggeth mine. The pyromorphite colours were enhanced by blue plumbogummite onseveral specimens and Michael thought that Roughtengill probably offered the world's bestof this combination. There was plumbogummite from Dry Gill which was almost turquoisecoloured. A very fine example of corkite (brown rhombohedra) with pyromorphiteovergrowths had been found at Mexico mine while a superb miniature size bluehemimorphite had been found last century at Roughtengill. Michael had travelledthroughout the country with his equipment to photograph these minerals, and we felt veryprivileged to see such high quality slides of exceptional specimens.

After refreshments there was an opportunity to examine some fine pyromorphite microsbrought by Peter Braithwaite and a fine selection of Wanlockhead slag minerals which hadbeen identified by X-ray diffraction by David Green. These specimens looked so muchbetter on the new Swiss microscope with trinocular head which John Bottomley let us alllook through! The next meeting will be held at Bircotes Library on Saturday 5 Julycommencing 2pm. Everyone is welcomed and if you need directions, please let me know.

West Midlands Branch Roy Starkey

A very successful meeting was held at Doug Morgan's house on Sunday 23 March, on thetheme of "Minerals of Clevedon Beach". The meeting commenced with a short illustratedtalk by Roy Starkey, and was followed by an in-depth practical session studying the variousspecies collected by members, much to the amazement of those who have not yet wallowedin the mud! There was plenty of free material to go around, and by 6pm everyone was ableto identify phosgenite - a relatively rare mineral for the amateur.

Details of the forthcoming field excursion were discussed, and it is planned to visit theGreenhow and Anglezarke area. Access and detailed information is being arranged by MikeBayley and Jim Wooldridge. Material collected on this trip will be discussed at the nextformal meeting which will be held on 14 September at 2 Speedwell Road, Birmingham. Thefollowing meeting will be on Sunday 30 November at the home of Ron Weaver, 3 MitchellRoad, Kingswinford, West Midlands. If you wish to attend either meeting, please phone Mikeor Ron in advance nearer the time. We will be delighted to see anyone living withintravelling distance of Birmingham. Please contact me if you require any help or assistance.

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South East Branch Elsie Hansford

In spite of the freezing weather and much snow, 28 members turned up at the 15 Februarymeeting and within minutes there was the usual buzz of activity with everyone having muchto talk about. Our meetings have always been informal, and we had some discussion onwhether we should introduce themes. Most seemed happy enough with the way things were,but on the suggestion of Peter Wallace, it was agreed that the next meeting should bedevoted to Minerals of Cornwall. Members are therefore asked to bring along Cornishspecimens, and slides of minerals or sites. Some hand-sized specimens would be appreciatedand set out on a display table, and perhaps some will bring suites of minerals from particularmines. The next meeting will be held on SUNDAY 1 June at 3pm and further meetings havebeen arranged for 17 August and 23 November, starting as usual at 3pm.

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PHOSGENITE FROM CLEVEDON Roy Starkey

A report on the above was recorded in the Proceedings of the Bristol Naturalists' Society(1984) 44. 13-14. Roy explained the rarity of this mineral in the British Isles, and explainedits occurence in barytes pebbles associated with galena. Crystals of phosgenite up to 1.5mmon edge had been collected and these occured in several forms - modified cube, complexprism, and a few elongated crystals with pyramidal terminations. The pebbles were found inthe mud on the beach behind large boulders below the Pier Hotel, west of Clevedon Pier(ref: ST4015 7185) and other minerals in them included aragonite, aurichalcite, azurite,brochantite, cerussite, chalcopyrite, covellite, cuprite, malachite and native sulphur. Theoccurence of phosgenite in beach pebbles was very similar to the classical Lauriumoccurence in Greece, where rare lead chlorides formed in ancient slags as a result ofreaction with seawater. The Clevedon occurence was analogous with the Newporth Beachdiscovery near Falmouth Cornwall but at Cievedon, phosgenite had not so far been found insitu.

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MINERAL SITE LISTS

In the last newsletter there was a suggestion that we should compile and publish a list of allthe Wanlockhead slag minerals which had been positively identified and there is some workgoing on in this direction. Geoff Deverell has suggested that it would be helpful forcollectors of Red Gill, Brandy Gill, Eaglebrook etc. material also to have listings of whathas been found. Lists are already available for some of these mines in the publishedmaterial but regular visitors are, no doubt, turning up new minerals. If these have beenconfirmed by crystallographic, optical or chemical methods etc. please let us know so thatthe information can be published. If site lists are submitted from published material, pleaseindicate sources and dates.

GOLD AT LOCH TAY

According to "Mining Magazine", two small Canadian companies are starting a drillingprogramme in the Loch Tay region, having acquired a licence to prospect 60,000 hectares.Last year they found four favourable zones for further drilling; Tomnadashan, Corrie Buie,Comrie and the River Almond. The latter is the most promising and will be tested withabout 3,000m. drilling with a similar amount being alloted to the other three zones.

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HOT ROCKS

Last September the Institution of Mining and Metallurgy organised a conference at StAustell concerned with the "High Heat Production (HHP) Granites, Hydro ThermalCirculation and Ore Genesis". The subject was topical because of the current investigationsinto potential geothermal resources of the Cornish Granites, and some forty papers werepresented. Most were the results of world-wide academic research but a quarter of thepapers dealt with various aspects of the Cornish granites and associated mineralisation. Oneof the papers dealt with Geevor mine and prospects along the coastal strip and offshore areaof St Just. There were also papers outlining investigations undertaken by the CamborneSchool of Mines in the deep borehole in the granite at the Rosemanowes site which lookpromising and may encourage further interest in the potential of Cornish granites to producehot water and/or metals. A volume of the Proceedings running to 593 pages has beenpublished by the Institution of Mining and Metallurgy, 44 Portland Place, London WIN 4BR,price £30.

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CORNISH TIN MINES CLOSURE

The collapse of the International Tin Council and the return to free market prices hasseriously affected all the Cornish tin mines, which are now under threat of closure. GeevorTin Mines suspended operations on 7 April and laid off most of their 358-strong labour force.The employees had been working overtime without pay since the beginning of the year, costshad been cut, and the company had sought aid for capital work to reduce costs further. Butthis was not forthcoming and the mine is on a care and maintenance basis. On 28 April RTZannounced that their Pendarves, Wheel Jane and South Crofty mines would have to close asthey were losing £1million a month. Employees have received 90 days notice, pendingclosure on 1 August. About 1,000 workers were employed at the three mines, and a further1,000 are indirectly dependent on the mines.

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RICHARD BARSTOW TIN COLLECTION

According to 'New Scientist' of 20 February 1986, Plymouth City Museums and Art Galleryhave launched an appeal to raise £100,000 to purchase the comprehensive collection of thelate Richard Barstow. The collection of cassiterite specimens from practically every knownsite in Devon and Cornwall is unique, and meticulously documented, and it is hoped that itcan be retained in this country.

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EXHIBITIONS/OPEN DAYS

The Micro 86 Microscopy Exhibition to be held from 7 - 11 July at the Bloomsbury CrestHotel, Coram Street, London WC1 will provide an opportunity for visitors to see the world'slargest selection of microscopes and accessories on display under one roof. Organised by theRoyal Microscopical Society in association with "Nature"; further information from theRoyal Microscopical Society, 37/38 St Clements, Oxford OX4 143.

Tickets for the Open day at the British Museum (Natural History) on Saturday 18 Octoberhave now been distributed by Roy Starkey to all who ordered. Any late applicants shouldwrite to John Fuller at the Museum, but availability is limited. The Open Day will consist ofthree 90 minute tours running at intervals throughout the day - visiting the facilitiesincluding the Russell Collection, the Mineral Gallery and History of the Collection,Cataloging procedures, the lapidary workshop, X-ray laboratory, electron microprobelaboratory etc. Additionally there will be two lectures by Dr R F Symes - "Minerals of theMendips" end "Aspects of Mineralisation of Central and North Wales". Roy is lookingforward to seeing you therel

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On the following day, Sunday 19 October, the British Geological Survey will be holding aPublic Open Day at their headquarters at Keyworth, Nottingham. Further details fromB.G.S. Keyworth, Nottingham.

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BOOK REVIEWS

"Gemstones" by Paul O'Neil. Time-Life Books - Planet Earth Series. 1984. Hardback 11" x9". 176 pages of Good Quality Paper. Price £10.95 from booksellers.

This is a well-constructed book, with a nice balance between text, diagrams andphotographs, which manages to cover virtually the entire field of gemstones; thoughinevitably detail is limited.

The content, in summary, includes the geological aspects of gemstone formation, the earlyexperiments and development of synthetics, and identification by examination of theinternal structure. Some rather nice photos in this section. Some of the more famousmines, past and present are reviewed with stones of owners, process of acquisition (or loss)and violent episodes associated with them; including that of the present day In the emeraldarea of South America. The diamond fields have special coverage, from history, colourfulpersonages such as Rhodes and Barrato, up to the latest major discovery In Australia.

I enjoyed this book, which was perhaps a little expensive for a non-reference work but I havecertainly seen worse value.

(Geoff Deverell)

"Noble Metals" by Jeffrey St John. Time-Life Books - Planet Earth Series. 1984. Hardback11" x 9". 176 pages of good quality. Price £10.95 from W H Smiths and other booksellers.

The composition of this book is similar to that on "Gemstones", the noble metals being gold,silver and platinum. The book explores atomic structure, crystalline forms and geologicalorigins. That is how volcanic activity brought the metals into the surface layers of theearth, after which faults and erosion formed placer deposits etc.

A considerable part of the book concerns mines and methods of extraction; together withstories of dealing and acquisition (sometimes devious) of mines. The history, particularly ofgold, is covered starting with ancient civilisations, through the middle ages (alchemists) upto the modern mines including the current activities in Brazil. There is good coverage ofobjets d'art, but rather too much on coins. The uses of these noble metals in industry arereviewed. I enjoyed "Gemstones" more but nevertheless this book is one I am pleased tohave.

(Geoff Deverell)

"Glossary of Scottish Mineral Species 1981" by H G Macpherson and A Livingstone.Published by Scottish Journal of Geology, Edinburgh and Glasgow. Softback 47 pages.Available from bookshop of Royal Scottish Museum, Chambers Street, Edinburgh. Price 25p.

Dr Harry Macpherson has kindly sent a copy of the above publication for the library of theBritish Micromount Society.

The glossary lists some 443 mineral names, together with ideal formula, crystal system,assemblage, locality and reference details. It began as a revision of the entries in Heddie's(1901) Mineralogy of Scotland but incorporates the result of more recent work. In additionto the glossary there are three appendices viz. minerals grouped anionically; mineralgroups; and minerals which were first discovered in Scotland. The location details areextremely valuable as are the sizes of crystals/grains, and the following paragraph is worthyof reproduction in full:-

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"Value of Mineral CollectionsCollecting from some mineral localities is now impossible; for example, we have seen oldlocalities which are now built over. When it is not possible to collect from the originallocalities recourse must be made to mineral collections. We have examined collections inother museums on a number of occasions. This has lead to discovery in some collections ofseveral minerals rare to Scotland. Examples are coquimbite, voltaite, roemerite, alunogenand tamarugite. The discoveries of alunogen and tamarugite were made on specimensborrowed from the British Museum (Natural History) and we wish to emphasise the greatImportance of accessible mineral collections in general. Without continued access to suchcollections a detailed mineral glossary like this could not be compiled. It is thereforeessential for mineralogists and geologists to have access to type and comparative specimensin museum collections. Such collections, even large and comprehensive ones, have to becontinually enlarged by fresh acquisitions - including donations of specimens from mineralcollectors and geologists - if they are to remain a vital source of reference material.Unfortunately we have found that some mineral collections have been poorly curated.Records are often inadequate, confusing or even missing. In some cases hundreds, and eventhousands, of mineral specimens have vanished, so that it is frequently impossible to checkon certain specimens mentioned in the literature. Had these collections remained intact,their specimens could now have been screened using modern analytical techniques, whenmuch new data would doubtless have been gained. In many cases, the material (oftenunique) has gone forever - with no chance remaining of acquiring similar material. Anyinstitute, department or private individual who owns a mineral collection, but cannot curateit properly should donate it (or sell it) to a large museum. The museum chosen should beseen to be fully equipped and able to maintain such valuable material for the benefit offuture workers in mineralogy"

(Eric Otty)

"Education In Chemistry" Volume 22. No. 6 (November 1985) contained an interesting articleon "Chemistry in the lake District - the Northern Orefield" by R Little and A Chapman. Itwas a very readable account of the Caldbeck Fells and adjacent areas and included amention of a school project to estimate the metal content and hence the value of theRoughtengill tips. This involved crushing a known weight of representative ,rock, andassaying for copper, lead etc. The ISSN number is 0013-1350 and the relevant pages are169-174.

(Roy Starkey)

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OVERSEAS NEWS

FinlandSevere members had the pleasure of meeting Leo Hogneval and his wife, Rita while theywere enjoying the London Show recently. In a further letter Leo says that if any collectorsgoing rockhunting to Finland want help, they should contact the Club at the followingaddress and they will arrange a local guide wherever in Finland they want to go.

Finnish Gem Hobbyists SocietyChairman, Kauko SairanenLansi-Kelmolantle 301750 VANTAAFINLAND

U.S.A. Frank E Ludeman, 11 Robin Crest Lane, Littleton, CO 80123 who is a geologist in theDenver, Colorado area is seeking trades end has a good selection of micro material to offer.These include cyanotrichite, cuprite, apophyllite with kinoite, wulfenites, vanadinite,descloizite, cerargyrite etc. from Arizona localities; topaz, covellite, garnet etc; fromColorado; Libethenite from Portugal; zeolites from Horsehoe Dam, Pheonix, Arizona; and

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West German material. Frank is primarily interested in metallic ore minerals (sulfo-salts inparticular) sulphates and zeolites, although he is interested in any good specimens.

The April 1986 list from David Shannon Minerals, 1727 W.Drake Circle, Mesa, Arizona85202, U.S.A. runs to twelve pages listing an extremely wide variety of specimens fromcabinet to thumbnail sizes from world-wide sources. Much of the Arizona materials, Davidcollects himself and his micro bags of material from named mines offer very goodmicromount material. The bags contain 21b or 21Ib and of special interest are the bags fromJ.C.Holmes Claim, Santa Cruz County, Arizona which contain vanadinites and descloiziteetc. This locality is described in the latest "Mineralogical Record" and the vanadinitephotographs are absolutely stunning. Other bags are available from 24 other sourcesincluding Humbot Mine, Arizona (malachite, cuprite, azurite) Padre Kino mine (wulfenites,cerussites, chiorargyrite etc.) Silver Bill mine (rosasite, hemimorphite, smithsonite,wulfenite etc). The bags cost $5.00 each and postage is $3.50. This is an excellent way forgroups of collectors to buy and share, or for the individual to obtain good specimens andbuild up a trading stock.

Canada The March 1986 list from Simkev Minerals, 942 Chevrolet Street, Oshawa, Ontario L164HB, Canada is particularly strong on offers of European minerals and topping the list isanatase from Manod quarry, Blaenau Ffestinlog! Eagiebrook, Cumbria, Cornwall, Devonminerals are offered in amazing variety and include some very rare ones - chloroxiphitefrom Merehead quarry, chalcoalumite from New East Wheal Russell, plumbogummite fromDry Gill. There is material from Czechoslovakia and Germany as well as South America andthe first offering I have ever seen of nealite from Thorikon beach, Laurium, Greece - namedafter the late Neal Yedlin, this mineral occurs as tiny yellow-orange crystals in slag usuallywith phosgenite/paralaurionite. This is very comprehensive listing of micro material atreasonable prices. The summer catalogue will specialise on German minerals and there willbe an Italian issue in the Autumn.

France Bertrand Duriez, 56 Rue de la Tombre Issoire, 75014 PARIS - FRANCE is seeking thefollowing rare minerals from Britain - Scotlandite, sweetlte, weddelite and sussanite. Inexchange he can offer:- imiterite from Imiter mine, Morocco (new mineral) Ag2HgS2,staczekite from Wilson Springs, Arkansas; a calcium potassium vanadate described inMineralogical Magazine Vol.48 pp 289-93.

Karibibite from Urucum, Brazil, crystallised for the first time.

All are crystallised minerals.

Bertrand is Head of the Secretariat of the French Micro Mineral Association.

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BAKEWELL ROCK SWAP 11/12th October 1986

This popular event will again be staged by the Peak Lapidary and Mineral Society at theMedway Centre, Bath Street, Bakewell, Derbyshire. Opening times will be - Saturday 11amto 5pm and Sunday 10am to 4pm. Table hire will be £6.00 for both days or £4.00 for one day.Full details are available from Les Fox, 4 Undercliffe, Bakewell, Derbyshire. Telephone:Bakewell 3542.

If you have not attended the event before, do make the effort, you will be rewarded with amost enjoyable weekend of chat, gossip, convivial company and many opportunities toacquire new material or dispose of your surplus rock etc. Buying and selling as well asexchange of material is permitted, and you do not have to book a table to participate - justcome along. See you there!

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BRITISH MICRO LOCALITIES No. 13

David Green

Isolation Mine (SK 154413)SnelstonNr AshbourneDerbyshire

The village of Snelston lies 2 miles SW of Ashbourne, and this collecting area is a smalldump no more than 5m x lOrn situated under some scrubby trees. The adjacent area is usedby Nestle Ltd as a dump for spent coffee grounds. Access must be by permission from theadjacent farm.

"Vets

44. - ot o;.Ksw-is

v:at CC.44 Cc. Or 0.....-cts.)

-be 4.109 1o—a 5,1-Z,ne.v.....t Its.savrase..3v.

Pa""4r-

Corx.J

Froce. 1-..cdee.c%.0.se

The following micro minerals were noted in about 15Ibs of material collected on the fieldtrip of the Northern branch of BMS on 5 May 1985:-

Sulphides

Calcite

Barite

Malachite

Azurite

Linarite

Wulfenite

- the sulphides galena, pyrite, chalcopyrite and sphalerite? disseminatedthrough the rock matrix. Nowhere were crystalline specimens found.

- as white pointed scalenohedral crystals in fissures and cavities in therock.

- thin colourless plates often pseudohexagonal in form proved to be barite.(Tested by determination of refractive index - 1.64 and lack of reactionwith nitric acid.)

- aggregates of rod-like crystals producing pleasing micros, especiallywhen dotted with clear barite plates. (Tested by crushing to powder andnoting complete solubility with effervescence in hydrochloric acid.)

- as a surface coating of dirty-blue colour - a post-mining formation?(tested by noting complete solubility with effervescence in hydrochloricacid).

- crystals of a brilliant blue colour in thin fissures on one piece of matrix.(Tested by noting "whiting" in dilute hydrochloric acid.)

- without doubt the most collectable material from this locality. Formsvaried from curved tablets to di-pyramids, the best specimens showingintense lemon-yellow crystals against a dark background. Both colourzonation and twinning on the C-axis were noted. Of particular interestwas a black mineral - perhaps wad - pseudomorphing wulfenite.

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Iron oxides brown stainings and coatings on calcite appear to be limonite while someof the black coatings could be geothite. Hematite also occurs.

Wad as an amorphous black stain/coating on calcite crystals.

Unknown No. 1 brown-black mineral with perfect conchoidal fracture associated withcalcite. Chemical tests indicate some iron, perhaps asphaltite orsphalerite?

Unknown No. 2 a part-formed tiny clear crystal on corroded galena, one of a kind andtoo small to test. Probably a lead secondary.

Of the above minerals, the more interesting secondaries occured in thin fractures and smallcavities in a fine-grained grey brown matrix. The site is still productive, and half a day'scollecting could provide a few good micros. The best time to go would be in Winter as thereis thick undergrowth to clear in the Summer.

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Microscopy Exhibition, Bloomsbury Crest Hotel, Coram Street, LondonWC1.

5th Annual B.M.S. Symposium, Leicester University.

Open Day - British Museum (Natural History).

Open Day - British Geological Survey, Keyworth, Nottingham.

Geological Assoc. Annual Re-Union and F.L.A.G.S. Exhibition.

Arnold Fisher Mineral Fair, Haywards Heath, Sussex.

Annual Bazaar - Amateur Geological Society, St Albans Church Hall, WestHeath Drive, Golders Green, London NW11 (opposite Golders GreenHippodrome). 11.15-3.30pm.

DIARY DATES

July 7-11

Sept 27-28

October 18

October 19

November 8

November 15

December 6

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NEW MEMBERS: We welcome to the Society the following new members:

Valerie Vicary, Maidenhead.Tel: 0628-29187

Philip & Sheila Groves, OxfordTel: 0865-87-2020

Mr Guy, Olton, W. Midlands

John Houghton, Greater ManchesterTel: 0942-882051

Paul Oldfield, BasingstokeTel: 0256-472205

John Powers, Gillingham, KentTel: 0634-49655

CHANGE OF ADDRESS

Michael Merry, "Aneth Lowen", Pink Moors, St Day, Redruth, Cornwall. Tel: 0209 821901.

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A HANDY MICROMOUNT HOLDER Steve Rust

Sometime ago I read in the Mineralogical Record about a device for holding micromounts atany angle under the microscope and thought members might like to try it.

Stage 1

Obtain a tennis ball, and some polyfilla. Cut the ball In half, and from one half cut about athird off and throw the small piece away.

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Stage 2

Mix the polyfilla and fill the half ball with it, carefully levelling off the surface. While stillwet, press the bottom of a micromount box into the centre, leaving about one-third of thebox protruding. When dry, remove the box. If the polyfilla comes out with it, stick It backin the ball with glue.

Stage 3" t le half ball into the other piece which acts as a stand.

We are rather thin on contributions this time and would like to hear from you. What haveyou found on the North Wales and Scottish field trips after specimens have been properlycleaned and examined? I know that plans are in hand for many members to join up oncollecting holidays during the summer and we would like to share your experiences. So dodrop us a line the deadline for the next issue is Mid-September. But before you doanything else, PLEASE COMPLETE AND RETURN YOUR APPLICATION FORM FOR THELEICESTER SYMPOSIUM TO MIKE ROTHWELL.

We look forward to seeing you there Keep smiling!

BRITISH MICROMOUNT SOCIETYNEWSLETTER EDITOR

Eric Otty6 Woodlands RoadPownall ParkWilmslowCheshire SK9 50B.

0000GO0000

15

Tie.and

Maar

April 1986

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B.M.S.

MAP SHOWING SPREAD OF MEMBERSHIP THROUGHOUT THEBRITISH ISLES.