Amber. A beautiful semi-precious stone, whose colours range from white, through yellow-orange to blue, red and black. It is a lightweight material and is used in ornamental pieces, folk medicine and rarely, perfume. Much of the amber mined today originates from rocks of the Cretaceous period or before, some as early as the Upper Carboniferous period, making it at least 65.5 to 320 million years old.
It is formed when sap oozes from a tree, pouring down to entrap insects, debris, feathers and other organic material; overtime and under the influence of heat and pressure, fossilising to become an object of high value.
Each amber stone containing organic material is a moment in time, perfectly captured, priceless to the science of paleogeography. The unfosslised specimans are helpful in constructing ecosystems and organisms of the ancient world, long gone. For this reason, pieces of amber containing complete specimens are rare and command a high price.
Amber is harvested at seas by hand, by diving or dredging. Ninety percent of amber is extracted from the ‘Kaliningrad Oblast of Russia on the Baltic Sea’*, although it can be found all over the world.
Sources:
http://en.wikipedia.org/wiki/Amber#Appearance
http://www.bernardine.com/gemstones/amber.htm