Amber

Amber

Amber has been common since the Stone Age. Amber beads, carvings, and amulets have been found all over northern Europe, Asia, and the Mediterranean. Natural amber may darken to brown after long exposure to air, and pressed amber may turn white. The composition of amber varies from sample to sample, as it is of organic origin. However, one sample of amber shows 67%-87% carbon, 9%-11% hydrogen, 15% oxygen, and 0- 0.46% sulphur.

There are many contrasting views as to why resin is produced, but it is considered a plant’s defense mechanism. In most cases, it’s to protect the tree from disease and injury (insects, fungi, etc cause these). Resin may be present at wounds, in fissures in the bark due to rapid growth, or simply a method of disposing of acetate.

Amber is amorphous, meaning it has no distinct crystalline structures. The transparency of amber depends on the sample, and varies from very clear to very opaque. The cloudiness can result from air bubbles trapped in the resin while it is still fluid. A fairly soft substance, amber rates from 1-3 on the Mohs scale (1-10, ten being hardest). This depends on the age of the amber- younger amber tends to be softer.

For its low hardness, compared to gems of similar hardness, amber can be remarkably tough or brittle. It tends towards conchoidal fractures (conchoidal meaning shell-like or curved). Amber has a resinous luster. It is also fairly buoyant. Amber will float on salt or sea water, with a specific gravity of 1,05-1,2. The opaque amber (containing more air bubbles) is generally less dense than clear amber.

Amber containing fairly high amounts of sulphur can fluoresce. The common fluorescent colours of amber are blue and yellow, although they are sometimes white, green, or orange.

Definition: A hard translucent yellow, orange, or brownish-yellow fossil resin, used for making jewelry and other ornamental objects.

Amber was formed millions of years ago, when plant resin was buried, as well as the insects, feathers and seeds trapped in it. This gooey mixture hardened to become amber. Most amber is from 30-90 million years old.

From the Latin ‘succinum’, meaning Amber, mineralogists have derived the word succinite. However, to other cultures Amber has been given specific names, due to its unique properties. For example, heated amber will burn, giving it the name ‘bernstein’ in Germany. In Greece, it was known as electron, due to its electric properties when rubbed with cloth. Amber feels warm to the touch and is a poor conductor of heat.

Amber has few scientific uses and its main finished products are jewelry, smoking articles, objects of art, and devotional articles. However, it is used practically in varnishes and lacquers. Its sweet smell makes it desirable to the perfume industry, and it is also used in rosin and turpentine. There has even been a case in which Amber was used as a building material for the now famous Amber Room (see above).

Bibligraphy/Links:

http://www.emporia.edu/earthsci/amber/amber.htm

http://www.google.ca/search?hl=en&ie=UTF-8&q=define%3Aamber+&meta=

http://www.amnh.org/exhibitions/amber/

TO CALCITE LINK:

http://www.oocities.org/esqsci/index.htm