Costa Rica, a tropical country of environmental and biological diversity, is located between Nicaragua to the north and Panama to the south in lower Central America. With Mesoamerica, Costa Rica is one of the two regions in which jade was extensively carved in Precolumbian times. The earliest evidence for worked jade, a pendant excavated in a burial on the Nicoya Peninsula, is dated to the mid-first millennium B.C., and jade continued to be carved into similar personal ornaments until approximately 700 A.D., when its use appears to have died out and/or been replaced by a fashion for ornaments of gold. The early pendant was made in the shape of a celt, or ax, with a top worked into a bird head and torso. Circular eyes and a wide downturned beak define the head above folded wings, in a basic version of what would be the classic Costa Rican bird pendant in jade. The bird-celt pendant would undergo many elaborations during subsequent centuries, all the while retaining these essential features.