Tiger iron 80.22 ct tongue cabochon 60.7 x 25.7 mm y31697

TIGER IRON, a mixture of iron oxide, tiger eye and hematite. In fact is related to what is called B.I.F. ( banded iron formation) ,a very old rocks made of layer of stromatolite and iron minerals. It's one of the oldest marine rocks dated over a billion years old. From Australia.