Adamite, (w. Smithsonite)

Mineral: Adamite, Smithsonite
Chemistry: Zn2(AsO4)(OH)
Size: 50 mm
Owner: Malcolm Southwood
Photographer: Malcolm Southwood

Large, translucent, terminated crystals (to 20mm) of yellow-green adamite (XRD confirmed), associated with snow-white crystals of smithsonite (XRD confirmed) displaying an unusual habit resembling elongated bundles of rod-like crystals. 

Although the adamite has been confirmed by XRD, its composition has not been determined. It's translucency and yellowish colour, however, suggest that it is reasonably close to the zinc end-member of the adamite-olivenite series.

The size and translucency of the adamite crystals is exceptional. 

An almost identical specimen in the collection at Harvard University (MGMH #117903) was acquired from Dave Wilbur in 1979, but unfortunately neither this specimen, nor the Harvard example, is attributed to a level number.