Amber/ Copal Nov-Dec 2018 Mineral of the Month
MINERAL OF THE MONTH – AMBER/COPAL
Taos Rockers focuses this month on the fossil resins known as Amber and Copal. The differences between Amber and Copal are addressed in a separate handout - Amber being a complete polymerization of the oxygenated hydrocarbons comprising the resin while in Copal the polymerization is only partially completed. The modern name for amber is thought to come from the Arabic word, ambar, meaning ambergris. Ambergris is the waxy aromatic substance created in the intestines of sperm whales and was used in making perfumes both in ancient times as well as modern. The term “amber” is loosely used to describe a scent that is warm, musky, rich and honey-like, and also somewhat earthy - emulating the scent of ambergris.
· Mineral: Amber (Copal)
· Chemistry: CxHyOz +/- S
· Crystal system: Amorphous
· Color: Yellow-orange-brown, pale lemon yellow, red, brown, nearly black; rarely blue or green
· Refractive index: 1.539 to 1.545
· Luster: Resinous
· Specific gravity: 1.05-1.10
· Mohs Hardness: 2-2.5
· Cleavage: None
· Fracture: Conchoidal
Amber is the fossilized, hardened resin of trees, ranging in age from less than a million to more than 300 million years old. Tree resin, initially a sticky semi-liquid, first hardens by losing volatile components, which evaporate into the air over periods from a few days to a few years. This is followed by a second stage of hardening in which the resin molecules polymerize (link with each other to form larger molecules), a process which can take anywhere from several tens of thousands of years to millions of years. After polymerization the amber becomes insoluble (or much less soluble) in organic solvents like acetone, toluene, alcohol, or gasoline. Young tree resins are sometimes known as "copal " or "young amber", but the term Amber should properly be limited to the ancient polymerized resins that do not become sticky again when a drop of organic solvent is applied.
Amber is heterogeneous in composition, but consists of several resinous materials more or less soluble in alcohol, ether and chloroform, associated with an insoluble bituminous substance. Amber comprises macromolecules formed by free radical polymerization of several precursors in the labdane family. These labdanes are diterpenes (C20H32) and trienes, equipping the organic skeleton with three alkene groups for polymerization. As amber matures over the years, more polymerization takes place as well as isomerization reactions, crosslinking and cyclization. Molecular polymerization, resulting from high pressures and temperatures produced by overlying sediment, transforms the resin first into copal. Sustained heat and pressure drives off terpenes and results in the formation of amber.
Amber is globally distributed, mainly in rocks of Cretaceous age or younger. True amber of lapidary quality comes mainly from the Baltic region (principally Poland and Lithuania), with some production also in Mexico (Chiapas), the Dominican Republic, and Burma. About 90% of the world's extractable amber is located in the Kaliningrad Oblast of Russia. Most copal comes from Colombia and Madagascar and is considered much too young to qualify as true amber. Copal-dealer Norcross-Madagascar claims that the Madagascar copal is almost completely polymerized (+/- 65% towards fossilization). Amber-dealer Aragon Enterprises claims that fossil evidence (flora) in Colombian copal dates the resin to 23 million years ago.
The composition of resins is highly variable; each species of flora produces a unique blend of chemicals which can be identified by the use of pyrolysis–gas chromatography–mass spectrometry. The overall chemical and structural composition is used to divide ambers into five classes. Baltic ambers are thought to be fossil resins from Sciadopityaceae family plants that used to live in north Europe. Resin from the extinct species Hymenaea protera is the source of Dominican amber and probably of most amber found in the tropics. The African and American (Colombia) copals derive from Leguminosae trees family (genus Hymenaea). Copals from Indonesia and New Zealand appear to be resins from trees of the genus Agathis (Araucariaceae family). It is improbable, however, that the production of amber was limited to a single species; and in fact a large number of conifers belonging to different genera are represented in the amber-flora inclusions.
Amber is unique in its preservation of parts of organisms not usually fossilized. Amber can contain fauna or flora caught in the resin as it was secreted. Insects, spiders and even their webs, annelids, frogs, crustaceans, bacteria and amoebae, marine microfossils, wood, flowers and fruit, hair, feathers and other small organisms have been recovered in Cretaceous ambers (deposited c. 130 million years ago). The oldest amber to bear fossils (mites) is from the Triassic (230 million years ago) of north-eastern Italy. The oldest amber recovered dates to the Upper Carboniferous period (320 million years ago).
Amber has been used since the Stone age in the manufacture of jewelry and ornaments, and to this day in the manufacture of smoking and glassblowing mouthpieces. Amber has long been used in folk medicine, perfumery and varnish making.
Some of the locales from which specimens of Amber or Copal are available at Taos Rockers are:
Baltic Sea area (esp. Poland & Lithuania)
Melody, in her book Love Is In The Earth, says Amber “allows the body to heal itself by absorbing & transmuting negative energy into positive energy...helps to calm nerves and to enliven the disposition". Copal is "used to activate the crown chakra...and to maintain physical consciousness...used in the removal of energy blockages".