Sinkankasite

Sinkankasite
Sinkankasite
General
Category	Phosphate mineral
Formula (repeating unit)	H 2MnAl(PO 4) 2(OH)·6H 2O
Strunz classification	8.DB.20
Crystal system	Triclinic
Identification
Color	Colorless
Crystal symmetry	Triclinic - pinacoidal H-M symbol (1) Space group: P1
Mohs scale hardness	4
Luster	Vitreous
Diaphaneity	Transparent
References	[1][2]

Sinkankasite, mineral formula: H
2MnAl(PO
4)
2(OH)·6H
2O, was named after John Sinkankas (1915–2002), noted author and mineral collector, Scripps Institute of Oceanography.^[3] It is triclinic; as colorless, bladed to prismatic crystals up to 4 mm in length, often as divergent, radial aggregates and as pseudomorphs after triphlyte crystals; occurs in the Barker pegmatite (formerly Ferguson pegmatite), east of Keystone, South Dakota, and in the Palermo pegmatite, North Groton, New Hampshire.^[4]

References

1. Mineralienatlas
2. Mindat
3. Burns P C, Hawthorne F C. 1995. "Sinkankasite." American Mineralogist, 80 (1995) p.620-627.
4. Mitchelll, Richard S. 1986. "Who's Who in Mineral Names; John Sinkankas." Rocks and Minerals. Volume 61 (1), page 28.