One outstanding greenish yellow sharp crystal of the extremely rare titanium-tellurium mineral winstanleyite from the type locality (Tombstone District, Cochise County, Arizona, United States of America) and only one of the three known localities worldwide. Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY 4.0
Winstanleyite
Winstanleyite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula TiTe⁴⁺₃O₈.
It crystallizes in the cubic crystal system (space group I2_1/a-3).
Key properties: Mohs hardness 4; specific gravity 5.57; Very pale yellow streak.
IMA symbol Wsn, IMA status: approved, named in 1979.
Very rare in strongly altered and pyritized granodiorite from the dump of a hydrothermal Au–Te-bearing ore deposit.
It is found associated with Jarosite, chlorargyrite, rodalquilarite, “opal”.
The mineral was named to honor Betty Jo Winstanley Williams (1934–), who collected the first specimen.