Amber occurs in a range of different colors. As well as the usual yellow-orange-brown that is associated with the color "amber", amber itself can range from a whitish color through a pale lemon yellow, to brown and almost black. Other uncommon colors include red amber (sometimes known as "cherry amber"), green amber, and even blue amber, which is rare and highly sought after.
Amber is globally distributed, mainly in rocks of Cretaceous age or younger. Historically, the Samland coast west of Königsberg in Prussia was the world's leading source of amber. About 90% of the world's extractable amber is still located in that area, which became the Kaliningrad Oblast of Russia in 1946.
Pieces of amber torn from the seafloor are cast up by the waves, and collected by hand, dredging, or diving. Elsewhere, amber is mined, both in open works and underground galleries. Then nodules of blue earth have to be removed and an opaque crust must be cleaned off, which can be done in revolving barrels containing sand and water. Erosion removes this crust from sea-worn amber.
Caribbean amber, especially Dominican blue amber, is mined through bell pitting, which is dangerous due to the risk of tunnel collapse.