Amber Types of Amber, Copal and Resin PDF

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Types of Amber, Copal & ResinTo a Piece of Amber Limpid lump with light refulgent. Tawny tinted, cold yet warm, Whence has come your mystic beauty, Your alluring wonderous charm? Are you blood of Forest Monarch Slain by the Storm King's might, Clotted in Earths cold bosom Through ages of Arctic night? Or the tears of Druid Maiden For a lover found untrue? Tell me the tragic story That is hid in the heart of you. Are you frozen sunshine, Chilled by a world unkind, Or the golden pearl of an Elfin Earl Whose castle none may find? I am the blood of Forest Monarch, I am tears of a Druid Maid I am congealed sunshine From the haunts where Elfins played. I am all of these and more than these, For a token of love am I, To be worn next the heart of your true love To prove her constancy. An amulet gainst grief and pain, Gainst sorrow, sin and care, For none may harm where I cast my charm Oer beauty pure and rare. Walter S. Park

There are many different types of fossilized resin found all over the world. Each deposit has unique chemical constituents but can physically appear almost identical. In some cases it is only through detailed chemical analysis that the geographic origin of the resin can be determined. The process through which resin changes into amber has been dealt with elsewhere within this site. In brief the process is as follows:

THE RESIN-AMBER CONTINUUM

It should be noted that although the rate of transition from resin to amber is shown as a linear process, in reality it is variable and not at all a regular transitional mechanism. RESIN Following its secretion the resin immediately begins to lose its original plasticity and harden. The resin is not termed copal because the polymerization has not yet adequately progressed. There are several forms of commercially exploited resin.

Ambergris can be mistaken for a form of resin but in fact is not. It is actually a product found in sperm whales. It is found within the animal's digestive tract and is thought to be the result of infection of which the ambergris is the animal's natural defense mechanism. It is sometimes found washed up on beaches or was cut from the animals when whaling existed as an industry. It is used as a fixative in the perfume industry. Arabic gum was farmed in the Middle East during the earlier part of the 20th century. This was a major source of industrially exploited resin. It was used as a varnish and also as part of some photographic development processes. Dammar is a gum obtained from trees in Malaysia and Pacific islands. The gum is commercially collected and turned into lacquer and varnish. Frankincense is derived from a single tree, the Boswellia Species. It purported to induce a soothing atmosphere when used as incense. The following link gives some interesting information on ancient frankincense trade routes which have recently been identified in the Yemmen. Gum lac sometimes called shellac is not a bi-product of any tree but an excretion of an insect Coccus lacca. This insect secretes a resinous coating onto its body that builds up on the bark of host trees. This sticky mass is then gathered, collected and refined. It is used commercially as a varnish. The picture to the left shows harvesting in the process on the island of Indonesia. Click on the picture to move to the site from which it originates. Kauri Gum was mined and collected on the North Island of New Zealand. It is a recently formed resin that is classified as resin or gum rather than copal. It was secreted by forests of Agathis Australis. These large forests have been reduced to sparsely distributed glades. The few remaining trees have acquired state protection under that countries law and may not be felled. (In some cases the visual appearance of the resin cannot be distinguished from many amber specimens. Kuari gum displays the same qualities of translucence, fracturing and pale yellow colouring as many Baltic amber pieces. It is certainly more fragile, breaking easily and prone to fracturing).This link provides more information about Kauri Gum. Mastic is a resin produced by the tree Pistacia lentiscus. The tree grows predominantly in Greece. It is used commercially as a varnish and type of glue. Myrrh is the resin product of Commiphora tree. It grows mainly in Arabia and Turkey and like frankincense is used as extremely aromatic incense. It is also used for its medicinal properties. Rosin is the principal resin product of various pine trees. It is collected and distilled and used as on various string instruments to create suitable friction contact between the bow and string.

Sandarach is a resin farmed in North Africa and extracted from Junipers. It is used commercially as a varnish.

COPAL Copal is a more mature form of resin. The word copal comes from the Spanish word copalli which means incense, a task for which copal can in fact be employed. Polymerization has now progressed significantly through the body of the resin. In some cases the surface of the copal has fractured and crazed due to the surface shrinkage prompted through the initial evaporation of the turpenes which also begins during this period. (The author has witnessed a piece of resin craze and fracture over a period of 3 months when a large translucent piece weighing more than a Kilogram was displayed in a shop window in full sunlight thus accelerating the entire process with extreme heating and climatic conditions). Distinguishing between copal and amber is a contentious issue amongst members of the amber community. There is no scaling system for assessing polymerization against age. This is because too many external factors affect the rate of molecular linking and consequently a variable rate does not lend its self to a linear time assessment system. Because of this the nomenclature of resin, copal and amber is not an absolute science yet. Significant copal deposits exist in Columbia, South America in the Santander province. This material is less than 1000 years old. Despite being younger than the New Zealand, kuari material that can be over 10,000 years old, it is called copal, whereas the kuari gum is not. This can be confusing but is reflective of the variable rate of change resin undergoes in different conditions. It is important to note that the kuari gum of New Zealand would appear to have experienced little heat or pressure in its development to date, consequently it has not matured to the same degree that many other younger deposits have. Although these other deposits (Colombian being principal among them) are younger they have acquired the major characteristics of copal which the kuari gum has not. Cynically, it might also be observed that the classification of material against the Resin-Amber continuum is not always applied with the scientific rigor it should receive. Copal deposits exist in:

Africa (North, East and West) - Borneo, Congo, Madagascar, Kenya, Tanzania, Zanzibar. Asia - Damar. Australia - Allendale Victoria. Baltic. East India. Indonesia. Israel. Japan - Mizunami. Malaya. Philippines. South America - Brazil, Colombia, Sierra Leone and the Congo. Sumatra.

The complete transition from resin to amber has to have two additional factors present: heat and pressure. Heat and pressure may support the process of polymerization and turpene evaporation but their full effect upon the formation of amber is not fully understood. Copalite or Highgate resin is a term given to an ancient fossil resin found in the London clay. It is not common but it has been recorded in several geological narratives on these deposits. It has been found in Highgate and Richmond,United Kingdom.

AMBER Having established the development of resin into copal and looked in some detail at resin and copal I would now like to look at the final product of this process, true amber and retinite. This final stage requires the evaporation of turpenes from within the body of the fossil resin itself. Many scientists refer to Baltic amber as succinite. This is because of the high levels of succinic acid present within it. Scientists have used succinic acid in part to determine whether a deposit should be called amber, a name which strictly should only be used to describe Baltic amber. Other fossil resins containing no succinic acid fall under the generic term of retinite. But amber has been applied and used as a generic description for nearly all of the worlds fossil resin deposits. Other titles have been given to ancient resin, even to sub deposits found within the major Baltic deposit. Some of these ambers and retinitis are covered in greater detail in Patty Rices Book. Baltic Region Origin Some of the following entries are less than satisfactory because of the lack of detail. I have however had to rely on old book references as some of these deposits no longer exist or have been long forgotten. Allingite A form of fossil resin discovered in Switzerland but extremely rare. Little is known about these deposits or even if it is still found. Beckerite (Named after one of the owners of the Stanten and Becker amber product company situated in the Baltic). Is much denser and harder than Baltic amber despite being found in associated deposits. It takes a poor polish but does not break as easily as Gedanite. Its botanical origin is speculated to be some form of Leguminous tree. (Rice - 1980) Delatynite Referred to in some scientific papers published in the former Soviet Block. No information available. (Rice - 1980)

Gedanite (Derived from the word Gedanum the old name given to Gdansk in Poland) Gedanite is found within the Baltic amber deposits themselves. It is somewhat lighter in colour than typical amber and much more brittle. Jewellers and craft persons do not use this form because of its poor working properties. It also posses much lower levels of succinite and for this reason is not thought to have originated from the tree Pinites succinifer, but rather Pinites stroboides. (Rice - 1980). Gedano-Succinite Gedano-Succinite has similar properties to Gedanite and was defined though not named by the Scientist, O. Helm in 1877. The primary difference between the two varieties is the level of succinic acid present, Gedano- Succinite has up to 2.2% present, Gedanite, none. This variety of amber is also extremely friable when compared to other varieties. Glessite (The name originates from the Aesti word for amber, Glessum) Derived possibly from some form of Angiosperm but being similar to Beckerite in appearance, its physical qualities differentiate it, being harder and also taking a polish. (Rice - 1980) Krantzite A resin originating within the coal mines of Saxony it is excessively soft and unworkable. (Rice - 1980) Schraufite Found frequently in association with lignite and jet deposits. The deposit is located in the Carpathian Mountains. (Rice - 1980) Stantienite (Stantien and Becker the 20th Century producers of amber derived products had this amber type named after one of their founding owners). In many ways similar to Beckerite and similarly found within the major Baltic deposits. It will take a polish but fractures too easily. (Rice - 1980)

Succinite (Named after Succinic acid which is present within this particular deposit). Succinic acid COOH(CH2)2COOH15 can be present from 3 - 8% by weight. Succinite is the correct name for the Baltic amber deposits situated from just off the East coast of England across to the shores of Lithuania. These deposits are huge and have been exploited now for hundreds of years.

It is still being mined or gathered extensively throughout the Baltic region. One of the most prolific mines is at the Palmnicken site in Russia which is still working and remains one of the largest producers. Records show that to date most, 90% of amber extracted is poor quality and requiring further processing into varnish. The remaining 10% is suitable for jewellers and artisan use. Amber also had its ancient uses, and amongst other things was used as a varnish for musical instruments and oil paintings. The following link to the Amberalchemy web site explains the musical connection in more detail. Shellac is also a commercial derivative product of amber, more details can be found by taking the link. Non Baltic Region Origin Almashite See the Rumanite entry for this section. Ambrite This is a fossilized resin originating in New Zealand but is not the kuari Gum for which the region is so rightly famous but a true fossil resin that occurs on the North island. It is extracted from lignite beds found on the North Island of New Zealand. Amekit This is fairly recent discovery of true amber located in South Eastern Nigeria. The source is located in Eocene clay sandstone of the Ameki Foundation which presumably gave this amber its name. Tree origin at this time is unknown. Burmite Burma up until recent years had been Chinas major source of amber. The Burmese had mined and dug for the amber which was then sold to Chinese traders who would sell on to crafts people who prized the gem for its qualities and mythical properties. The amber was extracted from the Northern parts of the country. The mining shafts were lined with bamboo canes sunk down 10 -15 meters through clay deposits. The Mineral Resources of Burma published in 1934 noted 200 pits aimed at extracting amber near the village of Shingban. Photographs from this period show these mines as potential death traps. The author is uninformed about the situation regarding amber mining within this region at the current time. Most records refer to activity up until the 1930s, but none later. The age of Burmite has been established as Eocene through indicator fossils present in the amber deposits. The tree origin has been determined as Nummulites Biaritzensis. Chemawinite Amber from the Cretaceous is rare, but Canada has some remarkable deposits originating from this age. Cedar Lake in Manitoba is probably one of the most commonly written about sites. The Cedar Lake deposits were found on the South West lakeside shore as washed and tiny pieces ranging from .5cm to 2cm in diameter. Highly fossiliferous by all accounts containing many examples of both flora and fauna.

Various scientific expeditions have brought back several hundred pounds of amber from this site. In the 1950s a project was set in place to begin commercial development of the site. The venture later failed. This site has now been lost to science because of the flooding of the area. The former lake side shore is now hidden beneath the new water level. Reports have been made of amber beginning to appear on the new higher shoreline. So far these reports have been unsubstantiated. Dominican Republic Amber Dominican Republic amber, probably the worlds second largest deposit, is following that of the Baltic amber region, strangely does not have a unique name but can be called amber because of the presence of Succinic acid though not to the same level as Baltic amber. It is commonly...