Fossil tree resin that occurs as irregular nodules, rods, or droplike shapes in all shades of yellow with nuances of orange, brown, and, rarely, red.
Milky-white opaque varieties are called bone amber. Hundreds of species of insects and plants are found as fossils in amber. Deeply coloured translucent to transparent amber is prized as gem material, and numerous ornamental carved objects and beads are made from amber. Amber has been found throughout the world, but the largest deposits occur along the shores of the Baltic Sea.