A polished kambaba jasper sphere from Madagascar, green and near-black with the rounded orb patterns that give it its nickname, crocodile jasper. It looks ancient, and its story is usually told wrong: it is widely sold as a fossilised stromatolite, but laboratory testing identifies it as a rhyolite, a volcanic rock, not a fossil at all. The circular "eyes" are radiating needles of amphibole minerals, which form in igneous rock, not in the sedimentary layers where real fossils are found. The confusion likely came from a mix-up with a similarly named place in Uganda.
Rock: Kambaba jasper (rhyolite; quartz, feldspar, aegirine, amphibole)
Also known as: Crocodile jasper
Origin: Bongolava region, Madagascar
Hardness: 6.5 to 7 on the Mohs scale; hard and durable
Treatment: None
Diameter: 8.26 cm
Weight: 805 g
Note: Acrylic stand included (not the stand shown in the photo).
You'll receive the exact piece photographed.