Well this is an exciting new find - meet the naturally iridescent pyrite with quartz from West Kalimantan (call ih man tan) Indonesia. Rainbow pyrite is always a treat - we’ve seen iridescent specimens from Brazil, Pakistan and Peru before - but never Indonesia. These pieces feature adularescence - a phenomenon caused by the reflection of light between thumb layers within the stone. In the case of these pyrites, the irridescence is caused from tarnishing by oxidation and molybdenum traces on the