This extremely rare and important little crystal is approx 3mm in size. It was a gift from Harvard to the AMNH in the mid-1900s (label included) and one should be able to reasonably suppose that, since the type material was residing at Harvard, this crystal comes from the type material or at least the same pocket - or why bother to give it as a carefully catalogued gift to their colleague? Ex AMNH exchanged into the collection of dealer/collector Lawrence Conklin.