Amber

Amber is the hardened resin of pine trees which has been fossilized over time. Generally a golden yellow to brown color, it is found in a number of places around the world, but the oldest deposits are primarily from the Baltic. There is a large supply of Amber lying on the seabed which often results in pieces being washed up on the beach after a heavy storm. Although the quality of Baltic Amber is especially good (see picture below), deposits can also be found in Italy, Burma (Myanmar-Burmite), Rumania (Rumanite), China, Japan, Dominican Republic, Canada, Mexico and even the United States.

 Amber's honey-like appearance lends itself nicely to many jewelry applications. It is lighter than it appears, with almost a plastic like quality. It can be lighted by a match and the resulting odor smells like incense. Amber can be sensitive to caustic solutions, gasoline, acids, alcohol and perfume. It is often found to have inclusions of air bubbles, fine hair lines and stress fractures. Occasionally, bugs and plant materials can be found within, but it's more common to find bugs included in reconstituted amber.
Substandard pieces or small chips of amber are often salvaged by melting them into larger pieces to create "reconstituted" amber. Unfortunately, some producers of these pieces will put modern day bugs within them to lend more perceived value. As a result, amber containing bugs are much more likely to contain some innocent bumble bee that may have recently visited your begonias than any mosquito that used to dine on dinosaurs.

 
Amber can be treated by heating which causes it's internal structure to explode, creating what is often referred to as "Green Amber" (shown above) which can be quite beautiful.

The Columbian Amber pictured above is younger than other types of amber deposits, but still holds much beauty.

Stats:
Color: Yellow, brown and other colors
Mohs' Hardness Scale: 2 - 2 1/2
Density: Average 1.05 - 1.09
Transparency: Transparent to opaque