Dark blue microcrystals of stringhamite associated to sky blue acicular crystals of whelanite — Photo: David Hospital · CC BY-SA 4.0
Stringhamite
Stringhamite is an IMA-recognized mineral species in the silicate class, with the chemical formula CaCu(SiO₄)·H₂O.
It crystallizes in the monoclinic crystal system (space group P2_1/c).
Key properties: specific gravity 3.16–3.18; optically biaxial.
IMA symbol Sgh, IMA status: approved, named in 1974.
A retrograde reaction product between copper-bearing solutions and diopside in diopside-magnetite tactites (Bawana mine, Utah, USA).
It is found associated with Thaumasite, tenorite, kinoite, calcite (Bawana mine, Utah, USA); kinoite, apophyllite (Christmas, Arizona, USA).
In honor of Bronson Ferrin Stringham (1907–1968), Professor of Mineralogy, University of Utah, Salt Lake City, Utah, USA.