Detailed information
Species
Phosphohedyphane, Dioptase
Dimensions
75 x 57 x 50
mm
Weight
136 g
Locality
Mindouli District Pool Department Republic of Congo
Condition
No recorded repairs
Phosphohedyphane is a very rare calcium lead chlorophosphate mineral, forming a solid-solution series with Pyromorphite which is much commoner. This colourful small cabinet specimen from the Mindouli District, Pool Department, Republic of the Congo is dominated by well-formed gemmy emerald-green Dioptase crystals partially lining an open cavity in porous gossanous matrix. It is within this cavity that two 1 cm wide, blocky Phosphohedyphane crystals sit, joined together. These are pale cream-green coloured and have a matt surface texture/lustre. Their shape is unusual - almost orthorhombic - and suggests that perhaps they are pseudomorphous after another lead mineral, perhaps Anglesite. The host rock and cavity are also coated and veined with a pale sky blue powdery mineral which is not identified, but is possibly Shattuckite. It is from the superb systematic collection assembled by the brothers Martin and Michael Günther (1951-2007 & 1956-2021).