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Ussingite

Ussingite
Ussingite-219785.jpg
Ussingite from Shkatulka pegmatite, Umbozero mine (Umbozerskii mine), Alluaiv Mt, Lovozero Massif, Kola Peninsula, Murmanskaja Oblast', Northern Region, Russia
General
Category Phyllosilicate minerals
Formula
(repeating unit)
Na2AlSi3O8OH
Strunz classification 9.EH.20
Crystal system Triclinic
Crystal class Pinacoidal (1)
(same H-M symbol)
Space group P1
Identification
Color pale to medium violet, reddish violet; sometimes barely tinted purple
Fracture irregular/ uneven
Tenacity brittle
Mohs scale hardness 6-7
Luster sub-vitreous
Streak white
Diaphaneity transparent, translucent
References

Ussingite is a silicate mineral with formula Na2AlSi3O8(OH).

It was named for Niels Viggo Ussing (1864–1911), Copenhagen, Denmark.


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Wikipedia

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