Locality - Tafelkop, Goboboseb Mountains, Brandberg Area, Dâures, Erongo Region, Namibia
Size – 85 x 53 x 24mm
Weight – 80g
This Namibian prehnite specimen displays light mint green, finely crystalline growth that makes up most of the specimen showing a captivating, druzy 'sugary' sparkling effect when turned in strong light. Two large, semi-cubic, icy white calcite cubes sit atop the prehnite, both nicely terminated with ridged texture and excellent lustre, and in one area a small growth of seaweed green epidote can be seen through the translucent crystals. Composed mainly of fine crystalline growth with minimal matrix, this specimen is a real beauty hailing from a desirable Namibian locality.
Prehnite was not only the first South African mineral ever to be described and named, dating back to 1788, but also the first to be named after an individual, its discoverer Colonel Hendrik von Prehn, a Dutch mineralogist and governor of the Cape of Good Hope Colony. It is a hydrated calcium aluminum silicate, light mint to vivid apple green in colour with a vitreous to waxy luster, and many specimens also display an attractive luminous translucenct quality. Typically forming in botryoidal masses of orthorombic, sheaf-shaped crystals, prehnite is particularly aesthetic, often creating unique, multi-mineral compositions alongside epidote, quartz and calcite. Until relatively recently, this mineral was quite a rarity and scarce on the market, though newly found deposits have made it more available and incredibly popular among both collectors and lapidary artists. Much of the classic, desirable prehnite originates from Africa, with Namibia, Mali and South Africa being the best producers of fine collectors specimens, though Australia, China, France and Jersey in the US are also good sources of the mineral.