Phenakite (drill-bit twinned)
Thumbnail, 1.7 x 1.3 x 1.2 cm
Mogok Valley, Burma

This is a rare twinned crystal of gem phenakite from a small find in Burma some years ago. Fine and colorless, it shows off a textbook, but rare, "drill-bit twin" termination. It is definitely worthy of any major thumbnail competitive exhibit case.