What Did Iron Really Look Like? Patination and Coloring Treatments on Iron and Steel

Materials and Manufacturing Processes, 24: 999–1006, 2009Copyright © Taylor & Francis Group, LLCISSN: 1042-6914 print/1532-2475 onlineDOI: 10.1080/10426910902988059

What Did Iron Really Look Like? Patination and ColoringTreatments on Iron and Steel

Brian Gilmour1 and Alessandra Giumlia-Mair2

1Department of Materials, University of Oxford, Oxford, UK2AGM Archeonanalisi, Merano, Italy

Over the past century, the powerful but mythical image of knights in shining armour, with bright polished swords to match, has dominated ourview of what ironwork looked like: that of a polished greyish-white metal. This impression is gained not only from descriptions and illustrationsin many books but is also obvious from even a casual walk around museum collections specializing in high status ironwork (such as the RoyalArmouries in Leeds). But a close examination of much of this ironwork is likely to reveal that this was not its original appearance. Many poorlypreserved patinated surfaces have been mistakenly removed by restorers and conservators wishing to improve the appearance of the objects intheir care, not realizing they were altering the appearance by removing surviving traces of the original surface.

However, it is possible to work out what much early iron or steelwork was originally intended to look like even if very little of the originalsurfaces survive. This can be done by the study of a combination of things: actual surviving traces, related decorative features (such as inlays),early descriptions, pictures, and even the use of inhomogeneous metal for certain objects or the making of composite ferrous artifacts. From thiswe can start to find out that much ironwork was actually intended to be either one or more colors, mostly in the range black (hence blacksmith)or dark grey to brown or blue, sometimes with one color intended to show up in contrast to another, or to a decorative feature such as an inlay.The probability that induced patination on iron surfaces was also intended to serve as a protective film is also indicated by some written sources.These issues need to be examined to promote a much better understanding of this little understood aspect of early ferrous metalwork, both to findout how and why it was intended to look originally and avoid bad decisions on how it should be cared for and displayed.

Keywords Etching treatments; Iron patination; Pattern-welded damascus; Steel patination; Watered crucible steel.

IntroductionThe original aspect of early ferrous metalwork represents

in archaeometallurgy a relatively unexplored field. What didobjects made of iron or steel actually look like? With thisquestion in mind, we began to look for clues. The aim ofthis article is to explore the intentional patination of ironfrom prehistory to the 19th century1, and to try and illustratehow the coloring or patination of iron or steel was done.Although not many early examples of patination of iron areleft, it is possible to combine the evidence from some thatdo survive with structural evidence from the examinationof less well-preserved artifacts, and with descriptions ordepictions from early manuscript evidence, to get a betteridea of how iron or steel objects were intended to look. Thisin turn can allow us to reconstruct an approximation of theoriginal appearance of iron/steelwork even where no traceof induced patination survives.

BackgroundOver at least the past century, the powerful but mythical

image of knights in shining armor, with bright polishedswords to match, has been one factor which has dominated

Received February 14, 2009; Accepted February 27, 2009Address correspondence to Brian Gilmour, Department of Materials,

Science-based Archaeology Group, University of Oxford, Oxford, UK;E-mail: [email protected]

1All dates refer to Common Era except where stated as B.C.E., beforethe Common Era.

our view of what ironwork looked like: in our imagination, itis a polished greyish-white metal. This impression is gainednot only from descriptions and illustrations in many booksbut is also obvious from even a casual walk around museumcollections specializing in high status ironwork. This isparticularly the case with museum collections specializingin arms and armor. However, a close examination of alarge part of the ironwork in these collections is likely toreveal that this was not how it was intended to look likeat all. In many cases, the remains of patinated surfaces,often poorly preserved, have been removed by misguidedor overzealous restorers and conservators, who did notrecognize how objects, which might show both patinationand rust, were originally intended to look. Thus the wish toimprove the appearance of the objects has in many casesled to a complete and erroneous change of appearance bythe removal of surviving traces of the original surface.However, despite the poor survival of the original surface

of ferrous artifacts, it is possible to work out what a largenumber of early iron- or steelwork was originally intendedto look like. This can be done by tracing down and collectinga combination of factors. Firstly, we can look for the actualsurviving traces of a patinated surface, but also for relateddecorative features, inlays, and applications in contrastingcolors, which imply the earlier presence of a dark patinatedsurface.There are also early written sources which give

descriptions or mention colored surfaces in differentcontexts, or early manuscript, and other illustrations ofvarious kinds, showing details which would otherwise have

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remained unidentified and invisible. Finally, the use ofinhomogeneous metal for certain objects, in particular theexploitation of different ferrous alloys in the making ofearly composite ferrous artifacts, can help us to reconstructthe look of objects, mainly weapons, which were clearlydecorated in various shades of color.From all these features, and from literary and

iconographical sources, we can find out that much ironworkwas actually intended to be either colored or evenmulticolored in a variety of nuances, mostly in the rangeblack or dark grey to brown or blue, or in different shadesof these colors.Even the name of the artisan who worked iron—the

blacksmith—suggests that the material which was beingworked was mostly of the color black. Sometimes, one colorwas intended to show up in contrast to another—such asblack/dark grey/grey against a pale whitish color—or toenhance the effect of a decorative feature such as an inlayin a yellowish or silvery color. The probability that inducedpatination on iron surfaces was also intended to serve as aprotective film is also indicated by some written sources.

A problem of modern perception: how wereferrous objects intended to look?

Changing perceptions—what we expect to see—and poorsurface survival have both played their part in why theappearance of early ironwork has been forgotten to a largeextent.One current misconception is that ironwork was usually

intended to be seen as a greyish-white metal and that thiswas the “color of iron,” although closer investigation revealsthat in many if not most cases it was never intended tolook like this. The classic examples are suits of armor andswords. It is easy to see how this can happen through acombination of factors: first the obsolescence of the objects,the techniques which were used to decorate them, theaccumulation of surface dirt and rust before they becamemore valued antiques, and finally, the overzealous cleaningwhich removed most surviving evidence of the accuratepatination treatments originally carried out on the pieces.If a misconception of how things should look is repeated

and reproduced often enough—perhaps by only very fewpeople; however, by people who are supposed to take careand to know about these objects—our wider perception ofhow things should look begins to shift and change.In the case of intentionally patinated ferrous objects,

we can be more specific. Poor preservation and/or lackof recognition of blackened (browned or “blued”) surfacesmay have encouraged this mode of thought and courseof action, particularly when patination of this kind wasbecoming progressively less used. Lack of recognition andbad restoration procedures go together, and even now thereis still a misguided belief among some restorers that black ordark surfaces were not intentional and should be removed.This is of course not just confined to iron and steel objects.There are horror stories relating to things such as earlynonferrous celestial globes which have been ruined by thecleaning off of their black patinated surfaces—originallyintended to contrast with the color of inlaid silver stars—often still coming to light. Also in the case of more

ancient objects, the artificial and carefully applied patinawas removed down to the bright metal. This happened, forexample, with the kneeling figurine of Tutankhamun, in theUniversity Museum, University of Philadelphia (E14295),which was probably cleaned before being sold and was latercovered with a modern dark lacquer, as demonstrated bythe analysts Fishman and Fleming [1], but the compositionof the body metal shows that it is made of hmty km–-theblack colored, artificially patinated copper alloy containingsmall amounts of gold, silver, arsenic, and iron, similar toJapanese shakudô [2].Inevitably, the progressive disuse of techniques such as

the intentional patination of ironwork has been accompaniedby the disuse of the terms employed to describe thepatinated surfaces. For instance “browning” (sometimescalled bronzing or blueing) was a very common patinationprocess in the 19th century—and was still being specified bythe British War Office for the surface finish for mobile fieldartillery up to the late 19th century2—but is now largelyforgotten. This has led to the use of confusing terminology.For instance “blueing” has been (and still is) loosely appliedto almost any dark patinated surface (such as those seen onguns) whereas blacking is usually more appropriate.

Evidence for the common patinationof iron surfaces

Bad restoration and overenthusiastic cleaning have beencarried out on all kinds of artifacts, plate armor being justone of them (Fig. 1). However, in the case of plate armor,it is often possible to find traces of the original patinatedfinish on the hidden corners or edges of a plate which hasremained under an overlapping plate. Thus although poorpreservation (corrosion and rusting) and misguided cleaningmay have done an irreparable damage, all may not be lost,and some evidence will often survive.There are also many other clues as to how ironwork

of various kinds was intended to look, and even writtendescriptions which show how some ironwork was still beingpatinated for surface preservation even as recently as thelate 19th century. This was the case of some of the smallerArmstrong guns—those developed for mobile field artilleryin ca. 1860–1880—for which the British War Office issuedofficial treatises (instructions with recipes) as to how thesurfaces of these guns were to be patinated (rather thanbeing painted) to yield a brown finish.It is probable that patination of iron may have originated

both for preservation and decoration. This was certainly stillthe case during the 19th century as seen in patination by“browning” which was very widely used for gun barrelsthroughout the century, especially for the spiral wound,pattern-welded wrought iron gun barrels known both astwist or (misleadingly) as “Damascus” barrels. This canbe seen in the many surviving shotgun (and other) barrelsof this period. The different decorative welded styles hasbeen described in different publications, most notably in thegun manual by William Greener (1835, and in the many

2Such as those preserved in the archives of the Royal Armouries,formerly of the Tower of London, but now centered in Leeds.

WHAT DID IRON REALLY LOOK LIKE? 1001

Figure 1.—Example of black/dark patinated suit of armor with inlays incontrasting colors, belonging to a series of preliminary illustrations of suitsof armor, made by the Greenwich Royal Armoury under Jacob Halder, whichmake up the “Almain Album” of armor designs [3], now in the collection ofthe Victoria and Albert Museum (redrawn by A. Giumlia-Mair).

subsequent editions over the next half century). Greener’sillustrations (Fig. 2) showed up as black and white, butalthough the patterns would have been visible much asdrawn the barrels throughout this period were invariablyfinished a rich dark brown color with a polished shinysurface finish.Patination by “browning” was much less used after this

twisted/welded form of gun barrel ceased to be made, soonafter 1900. Patination by blueing/blacking has also beenused for many centuries and continues to be used to thepresent day, particularly in the small arms industry, butalso for treating small iron/steel components, because itreduces the glare to the eyes of the shooter, when lookingdown to the gun. The gunsmiths coated the parts to beblued in an acid solution, so that they rusted uniformly.Then the parts were immersed in boiling water to removethe solution residues and stabilize the patina. The rust wasfinally brushed off to give a deep blue finish to the gunparts [4].

How ancient are surface patinationtechniques for iron?

We suspect them to be very ancient—possibly, likewelding, going back to the beginnings of the use of iron—but how can we test the antiquity of this technique?There are many examples in museum collections ofbrowned/blued/blacked iron/steel surfaces dating back tothe beginning of the 16th century but, largely because ofcorrosion, far fewer survive from the 15th century, and verylittle from earlier periods. But there are various clues.

Evidence from early surviving objectsand written sources

A large decorated later Iron Age spearhead (ca. 200–50B.C.E.) found in the River Thames, shows a pair of incised

Figure 2.—Different varieties of pattern-welded “damascus” shotgun barrels as illustrated in Greener 1835.


Figure 3.—Iron Age spearhead (200–50 B.C.E.) found in the River Thames(British Museum collection).

Figure 4.—Late Roman ceremonial spear or lance head recovered from theRiver Moselle at Trier, dated to the 4th century (photo courtesy RheinischesLandesmuseum Trier).

yellowy copper alloy attachments on each side. This piecerepresents an excellent example, as it seems to have beenintended to be dark patinated to obtain a contrast with thecopper-based applications. Possibly traces of a blackenedsurface survive in one area near the central rib (Fig. 3).A very similar case is that of another, slightly later,

spearhead. It is an almost perfectly preserved Romanceremonial spear or lance head recovered from the RiverMoselle at Trier, dated to the 4th century. Also this objectwas found with its inlaid brass and copper pieces contrastingwith the glossy black patinated surface of the iron (Fig. 4).A much more complex object dated to the Roman period

is the long swords, found at South Shields (Roman Arbeia),the main supply fort near the east end of Hadrian’s Wall,together with other four pattern-welded long swords andfittings, placed under a rampart extension as a votiveoffering in 208 C.E. [4]. The Arbeia sword is pattern-weldedin a similar way to the first (as in Fig. 5) of two roughlycontemporary Roman swords found during archaeologicalexcavations at Canterbury, Kent in 19773 [5, 6].The same Arbeia sword was also discovered (on X-ray) to

have two rather crude, chiselled brass inlays, one on eitherside of the blade, representing Mars, the Roman god of war,and an eagle flanked by two standards (Fig. 6). Copper-based inlays would not make much sense on a light coloured

3This sword from Arbeia has not yet been metallographicallyinvestigated, but its pattern-welded was discovered during X-radiographicexamination at the British Museum Research Laboratory in the early1950s, although this work has yet to be published.

Figure 5.—Diagrammatic reconstruction of the composite pattern-weldedferrous construction of two long swords (spathae) found during excavationwork at Canterbury Castle, Kent in 1977.

silvery-grey surface, in particular next to a pattern-weldeddecoration.Some contemporary texts in Latin seem to suggest that

iron was normally seen to be black, and this can be linkedto the finds inlaid with metals in different colors.In particular, in the Historia Augusta, there is a

description of the scale armor of Maximinus’ father, whichwas suddenly seen as being of a purple color, instead ofbeing covered as usual of ferrugo (Historia Augusta IuliusCapitolinus, Vita Maximini, II, 4). The purple color of hisarmor signifies that his son was destined to be emperor andis mentioned as being in contrast with the common colourof armours, covered by ferrugo.In his commentaries of Vergilius’ Georgica, Servius

discusses and explains the word ferrugo as follows: “In theproper sense (the word means) iron rust, (or) the darker(blackish) variety of Spanish purple, (or) the blackness ofiron or iron filings.” proprie ferri scabies, purpura nigriorHispana, obscuritas ferri aut ferri rasura (Servius, Verg.,Georg. 1, 467). (Transl. by the authors.) The idea that ironwas seen as being normally of a blackish or very dark coloris clearly expressed.On iron objects, a black patinated surface with contrasting

pale metal inlays was probably very common. This fact isalso implied in cases in which the iron surface is much lesswell preserved, but inlays do survive. This can be seen onobjects of various kind, for instance on a Roman iron knifefrom Augusta Vindelicorum (Augsburg), dated to the 2ndcentury C.E. The knife shows an intricately decorated ironhandle, inlaid with silver wire (Fig. 7), which would nothave contrasted with a polished silvery-grey surface, butlooks very attractive against the dark surface. Another goodexample of patinated and inlaid object is a decorated ironplate from a 2nd century Roman wagon from Budaörs (inHungary, near Budapest) with an elaborate design made upof inlaid brass pieces.Possibly from the same region comes an even more

elaborate example, this time a late Roman (3rd/4th century)sella curulis (folding camp stool) made of iron decoratedwith copper and brass, and with a silver central boss (Fig. 8).Many examples of this kind are known in the early

Middle Ages, for example in Lombardic contexts allover Central Europe, in the Alps, and in Italy. Blackpatinated iron decorations, inlaid with silver and brass wires,were employed for horse fittings, long sword fittings, beltornaments, and clasps and became very common in the6th–7th c. C.E.Thus we can sometimes see the evidence where it is

unusually well preserved, but in other cases it is alsopossible to infer the appearance of patinated iron/steel


Figure 6.—Copper-based inlays on either side of the sword from Arbeia. The Roman god of war Mars is represented as Roman soldier. On the other side, theRoman eagle and two standards are visible (photos courtesy British Museum).

Figure 7.—Roman knife from Augsburg, iron inlaid with silver wire, 2nd c.C.E. (Photo A. Giumlia-Mair)

surfaces from manuscript illustrations or descriptions andlink this to inlays still visible on the surface of theobjects themselves. Different color nuances were also givento particular kinds of iron objects, mainly weapons, byexploiting the combination of various ferrous alloys. Thiswas achieved either by welding together different typesof iron and steel in one composite artifact, or by forgingan inherently inhomogeneous steel alloy—made from a

Figure 8.—Detail of Roman sella curulis (folding camp stool), iron inlaidwith brass and copper, with silver details, Western Roman province, perhapsDacia, late imperial period, now in the Levy/White collection, New York.(Photo Nimkin [7]).

crucible steel with specific properties—to yield a surfacewith contrasting colors or shades of grey.The idea for the exploitation of decorative watering

for crucible steel swords, daggers, and the like, maywell originally have come from ferrous metalwork ofpre-crucible bloomery origin, quite probably from theknowledge of early examples of pattern-welded swords.Indeed, some central European examples of pattern-weldedswords have been dated to the 5th or 4th century B.C.E.These swords have complex composite blades made bywelding together pieces of different ferrous alloys. In thisway the surfaces of the blades yield different patterns


Figure 9.—Lombardic belt fittings from Nova Gorica (Slovenia) 7th c. C.E.Iron with silver and brass inlays [15].

after the final polishing and etching treatments. In the caseof a few examples of late Iron Age swords, the surfaceis preserved well enough, and it shows that the swordwas polished and then etched to reveal the pattern of thecomposite structure of the blade (Fig. 10).Many examples of post-medieval “watered” crucible steel

objects mostly swords and daggers of Iranian or Indianorigin survive and can be seen in museum collections,although there are very few from before the 16th centurystill with their watered surfaces.However, it is clear from medieval written sources that

crucible steel swords with visible patterned surfaces—referred to by the allusion to watering—were alreadypopular in the pre-Islamic era [8, 9], and these wateredblades continued to be made until well into the 19th centuryas can be seen from the many surviving examples (Fig. 11).There is no reason to think that the origin of this kind ofvisible decorated surface cannot go back to the beginnings

of crucible steel making, possibly as early as the 3rd or 2ndcentury B.C.E. and the immediately following centuries,when the manufacture of this steel is described, and probableexamples of the steel itself are known [10, 11].Some early manuscript illustrations actually show that

welded patterns were intended to be visible, as in the caseof a 10th century Anglo-Saxon illustration which seems toshow barbed spearheads, although these did not exist at thistime [Fig. 12(a)]. However, the structure of the (by nowrelatively common) large pattern-welded spearheads of thisperiod has been found to be such that, when etched, theywould have the appearance of being barbed [Fig. 12(b)].Early descriptions of the patterns observable on swords alsoexist: there are several in the early poem Beowulf, and thereis a very detailed description in the Norwegian Thioric’sSaga4 describing a snake running down the central part ofthe blade.It has been suggested that snake descriptions could be

explained as the application of poetic licence, but a 6thcentury example of just this kind of sword was found morerecently in a 6th century Anglo-Saxon cemetery at WestHeslerton in Yorkshire [12].This sword shows that the comparison to a snake would

have been a very good description of the appearance ofcomposite pattern welded blades of this form, once they hadbeen polished and etched to reveal the decorative compositesnake-like structure (Fig. 13). Various very complexcomposite iron/steel objects—mainly swords, daggers, andspearheads—are easier to understand when a patinatedsurface appearance is taken into account.

Patination processes: how was itdone/what was used?

Kuftgari is a rather famous technique for the productionof colored and inlaid steel objects and was practiced inIndia on armors and weapons [13]. The colored steel isinlaid with silver or gold wire. The entire surface is covered

4This Norwegian saga was not written down until about the 13thcentury, but the content–names, etc.—would appear to derive from muchearlier, suggesting it to be set in the 6th century.

Figure 10.—Late Iron Age sword from Orton Meadows, near Peterborough, Cambridgeshire with a well-preserved pattern welded blade, the central part of whichhas been etched to reveal the pattern, the edges having been resist–protected, although the structure of these is the same (in the collection of Peterborough Museum).


Figure 11.—Watered crucible steel blade of an early 16th century C.E. single edged sword (kiliç) (photo courtesy Royal Armouries).

Figure 12.—(a) Eleventh century C.E. Anglo-Saxon illustration seeminglyshowing “barbed” spearheads. (b) The depiction of these seemingly ‘barbed’spearheads probably derives from the “barbed” pattern visible on contemporarypattern-welded spearhead such as the one shown on the left here (from theRiver Thames at Kempsford).

with thin parallel grooves cut with the chisel, so that thewires can be inlaid anywhere on the objects. After theinlaying, the surface is cleaned with sand and lemon juiceand then rubbed smooth with charcoal first and then witha steel burnisher. The object is finally held with tongsover a flat ceramic dish filled with charcoal until the metalturns bluish-black, while the silver wire remains white andshiny. The bluing temperature is of around 280–300!. Thissimple procedure is considered a traditional local techniquealso elsewhere, for example in some places in Mexico[13], where blued steel buttons, buckles, stirrups and spurs,saddle fittings, and knife handles, inlaid with silver andgold, are produced. The wide diffusion and the simplicityof this technique suggest that this was one of the methodsemployed from early times; however, there were also otherways to color iron and steel.Patinating agents used more recently in Europe are known

by the color they imparted, hence bluing, blacking, andbrowning, and possibly this was always the case. In theMiddle-Eastern and Iranian region, the chemical patinationor etching substance zaj/zag/zagh was known for manycenturies. The first who mentioned it in the earlier 11thcentury was Abu Rayhan al-Biruni, who says that zajfrom Bamyan (central Afghanistan) was the best [8]. Zajwas analyzed as early as 1818, when it was found toconsist of impure iron sulphate, probably derived fromthe decomposition of the sulphide mineral iron pyrites [8].Similar patinating/etching chemicals must have been used inEurope for many centuries. After the beginning of the 19thcentury, the best known patinating agents are probably thoseassociated with the treatment of gun barrels by blueing,browning, or blacking. Like Zaj, these result in inducedoxide coatings designed to produce different surface effectsdepending on what is in them and how they are applied.In modern times, several different chemical formulas have

been developed for producing a dark patina on iron and steel[14]. The most common is a mixture of nitric acid, coppersulphate, and selenious acid diluted in water, and used toachieve a black color by repeatedly dipping the objects tobe patinated in the warm solution below the boiling point. Afurther preparation to achieve a black finish is a mixture ofcaustic soda, potassium nitrate, and potassium nitrite dilutedin water and used at the boiling point.


Figure 13.—Diagrammatic reconstructions of a pattern-welded sword from a grave in the 6th century C.E. cemetery at West Heslerton, Yorkshire, showing theoverall appearance of the surface of the blade (top) and a more detailed view of the structure of the blade (below).

A blue color can be obtained with an aqueous boilingsolution of sodium thiosulphate and lead acetate or, at roomtemperature, with potassium chlorate, mercuric chloride,and alcohol diluted in water. In most cases, wax, neutral oils,or paraffin are applied as last finish, to achieve a lustroussurface.

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Technical studies. Archaeometry 1980, 22 (1), 81–86.2. Giumlia-Mair, A.; Gaboda, P.; Györy, H.; Vozil, I. Two statuettes

with hmty km inlays in the Fine Arts Museum in Budapest. InMetals and Societies; Kienlin, T.L., Roberts, B. Eds., Studiesin honour of Barbara S. Ottaway. Universitätsforschungen zurprähistorischen Archäologie, Habelt, Bonn, 2009.

3. Williams, A.; de Reuck, A. The Royal Armoury at Greenwich1515–1649: A History of its Technology; Royal Armouries:London, 1995.

4. Angier, R. Firearm Blueing and Browning; Stackpole Books,Arms & Armour Press: London, GB, 1936.

5. Gilmour, B. Victims of Crime? Ferrous Technology andOrigins of Two Pattern-Welded Long Swords From DurovernumCantiacorum (Canterbury, Kent). Proceedings of the 2nd Intern.Conference Archaeometallurgy in Europe, Aquileia, June 2007.Digital publication on CD, 2007, AIM: Milan.

6. Allason-Jones, L.; Miket, R. The Catalogue of Small Findsfrom South Shields Roman Fort; The Society of Antiquaries ofNewcastle upon Tyne, 1984.

7. Simon, C. An Inlaid Curule Chair in the Leon Levy and ShelbyWhite Collection. In I Bronzi Antichi: Produzione e tecnologia;Giumlia-Mair, A. Ed., Atti del XV Congresso Internazionale suiBronzi Antichi, Grado-Aquileia 22–26 maggio 2001, éditions M.Mergoil, Montagnac, New York, 2002; pp. 549–553.

8. Hoyland, R.; Gilmour, B. Medieval Islamic Swords andSwordmaking: Kindi’s Treatise ‘On Swords and Their Kinds’;Gibb Memorial Trust: Oxford, 2006.

9. Smith, C. A History of Metallography: The Development of Ideason the Structures of Metals before 1890; MIT Press: Cambridge,Massachusetts, 1988.

10. Giumlia-Mair, A.; Jeandin, M.; Ota, K. Metal trade betweenEurope and Asia in Classical Antiquity. In Proceedings ofthe 6th International Conference Beginnings of Use of Metalsand Alloys; Mergoil, M. Ed., Beijing, September 2006, USTB,Archetype Publications: London.

11. Allan, J.; Gilmour, B. Persian Steel: The Tanavoli Collection;Oxford University Press: Oxford, 2000.

12. Gilmour, B. A sword from grave G 74. In West Heslerton: TheAnglian Cemetery; Powlesland, D., Haughton, C. Eds., LandscapeResearch Centre: Yedingham, Yorkshire, 1999, 120–123.

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15. Ciglenecki, S. Langobardi na poti v obljubljeno de!elo. In Zakladitisocleti, Zgodovina Slovenije od neandertalcev do Slovanov;Bo!ic, D., Pavlin, P., Eds.; Narodna in univerzitetna knj!nica:Ljubljana, 1999, 346–348.

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What Did Iron Really Look Like? Patination and Coloring Treatments on Iron and Steel