Amber stone isn’t a true gemstone. Rather, amber is fossilized tree resin that can be 30 to 90 million years old. Amber has been highly prized for its warmth and beauty. Traditional amber stone is a hard, golden-yellow to brownish-yellow translucent resin. In rare forms it can be blue or green. Because amber was created by living trees, the stones are often found with interesting inclusions like insects, seeds, feathers and bubbles.