- Dioptase (gem crystals)
- Mbumba, Pimbi hill, Mindouli, Pool Department, Republic of Congo
- Thumbnail, 2.5 x 2.5 x 1.0 cm
- Ex. Paul Otto
This fine thumbnail features gemmy and lustrous, dark emerald-green Dioptase crystals in a very aesthetic cluster. With proper lighting, you can see the gemminess expressed as the green 'fire' so desirable in good Dioptase crystals. Pimbi Hill, Mindouli, Republic of Congo has put out a small number of outstanding Dioptase specimens, with material of this quality dating from the 1950s to mid-1970s. A very fine thumbnail, and even better in person.