Kinoite

Kinoite
General
Category	Sorosilicate
Formula (repeating unit)	Ca2Cu2Si3O8(OH)4
Strunz classification	9.BH.10
Crystal system	Monoclinic
Crystal class	Prismatic (2/m) (same H-M symbol)
Space group	P21/m
Unit cell	a = 6.99, b = 12.88 c = 5.65 [Å]; β = 96.18°; Z = 2
Identification
Color	Transparent deep blue
Cleavage	excellent {010}, distinct {001} and {100}
Mohs scale hardness	​2 1⁄2
Luster	Vitreous
Diaphaneity	Transparent
Specific gravity	3.13 - 3.19
Optical properties	Biaxial (-)
Refractive index	nα = 1.638 nβ = 1.665 nγ = 1.676
Birefringence	δ = 0.038
Pleochroism	Strong
2V angle	Measured: 68° , calculated: 64°
Dispersion	relatively weak

Kinoite (Ca₂Cu₂Si₃O₈(OH)₄^[1][2] or Ca₂Cu₂Si₃O₁₀·2H₂O^[3]) is a light blue copper silicate mineral. It is somewhat scarce. It has a monoclinic crystal system, vitreous luster, and is transparent to translucent. It can be found in the Santa Rita Mountains, the Christmas Mine at Christmas, Arizona and a few other copper mines. Kinoite is popular with mineral collectors. Kinoite was named upon its discovery in 1970 after the pioneer Jesuit missionary Padre Eusebio Kino who worked in Arizona, Sonora and Baja California.

References

Wikimedia Commons has media related to Kinoite.