Andyrobertsite , Calcioandyrobertsite Locality: Tsumeb Mine (Tsumcorp Mine), Tsumeb , Otjikoto (Oshikoto) Region, Namibia ( Locality at mindat.org ) Size: 3.3 x 2.5 x 1 mm. A piece of the only known specimen of Andyrobertsite and Calcio-andyrobertsite (see the Mineralogical Record, Vol. 30, #3, May-June, 1999). The color on this single crystal ranges from a spectacular royal blue (Andyrobertsite) to a beautiful and intense green (Calcio-andyrobertsite), with a superb luster to match. Both are valid species in a series. This specimen was peeled off the TYPE SPECIMEN and so is a HOLOTYPE. This means that it is a validated piece from the type descriptive specimen listed in the scientific records for the species. It is accompanied by the label from William Pinch, who gave it to Charlie as a gift when Bill found out that he had a new species. Bill bought the specimen (said to have been found about 1950) years ago and to this day it is the only one that has turned up. This is a rare trim he peeled off it, for his friend, with documentation. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Calcioandyrobertsite
Calcioandyrobertsite is an IMA-recognized mineral species in the arsenate class, with the chemical formula KCaCu₅(AsO₄)₄[As(OH)₂O₂]·2H₂O.
It crystallizes in the orthorhombic crystal system (space group Pnma). It is a member of the Andyrobertsite structural group.
Key properties: Mohs hardness 3; specific gravity 4.011; Pale blue streak; Vitreous luster; optically biaxial.
IMA symbol Carb, IMA status: approved, named in 1997.
On a single specimen from a weathered polymetallic mineral deposit.
It is found associated with Cuprian adamite, zincian olivenite, andyrobertsite, tennantite.
The prefix, calcio, designates the calcium analog of andyrobertsite.