Detailed information
Species
Cobaltkoritnigite, Erythrite
Dimensions
43 x 42 x 30
mm
Weight
84 g
Locality
Bou Azzer, Tazenakht Ouarzazate Province Morocco
Condition
No recorded repairs
The mines at Bou Azzer in Morocco have undoubtedly produced the world's finest Erythrite crystals but they have produced some of the best Cobaltkoritnigite specimens too. The former is a hydrated cobalt arsenate and the latter - hydrated cobalt arsenite hydroxide - indicating a very slight shift in the geochemical conditions during growth within the supergene secondary environment. This lovely brightly coloured miniature specimen features very glossy deep pink-purple bladed monoclinic Erythrite crystals (to 3.5 mm long) lining a 1.4 x 1.4 cm open cavity in heavily oxidized Skutterudite. Alongside this cavity - and actually infilling a much larger cavity - is more Erythrite, but also finely crystallized silky bubblegum-pink acicular Cobaltkoritnigite in areas extending to 1.4 x 1 cm. Under magnification this Cobaltkoritnigite is extremely well-crystallized and world-class in extent and quality. A very pretty rarity from the superb systematic collection assembled by the brothers Martin and Michael Günther (1951-2007 & 1956-2021).