Shigaite
Mn7Al4(SO4)2(OH)22· 8H2O

     Shigaite, formerly UK # 76, is relatively rare at MSH.

PHYSICAL CHARACTERISTICS:

Color is usually pale brown.
Luster is vitreous.
Diaphaneity is transparent to translucent.
Crystal System is hexagonal, R3.
Crystal Habits include tabular hexagonal crystals forming rosettes.
Cleavage {0001} is perfect.
Fracture is flexible.
Hardness is 2.
Specific Gravity is approximately 2.3 g/cm3.
Streak is very light yellow to white.
Associated Minerals include kupletskite, microcline and UK # 58.
Distinguishing Features: Cystal habits
Origin: Named in 1985 after its discovery locality, at the Ioi mine, Shiga,
   Honshu, Japan.

CLASSIFICATION:

Dana System
# 31.1.2.1

Strunz Classification
# VI/D.14-22

REFERENCES:
Dana 8:639 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

MSH
¤¤¤

PE
¤¤

AP
--

MX
--

SS
--

MC
--

HF
--

BR
--

SX
--

FR
--

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