- Miniature, 4.8 x 3.4 x 2.2 cm
- Djebel Hamimat, Constantine, Algeria (TYPE LOCALITY, 1851)
- Ex. Martin Zinn
A large plate of sharp crystals to 4mm, from this type locality for the species. I believe they were found during expeditionary work by French geologists, and much of this was brought back and put into French museums and dealerships at the time. Large specimens are very rare - usually I see only thumbnail loose crystals on the market.