Rectorite

General Information:
 Chemical Formula:
(Na,Ca)Al4(Si,Al)8O20(OH)4·2(H2O)
 IMA Status:
Approved IMA 1963
 Locality:
Blue Mountain district, Marble, Garland County, Arkansas, USA.
 Name Origin:
Named for E. W. Rector (1849-), legislator and lawyer of Hot Springs, Arkansas, USA.
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
yellowish white or white.
 Habits:
Earthy - Dull, clay-like texture with no visible crystalline affinities, (e.g. howlite)., ,
 Hardness:
1-2 - Between Talc and Gypsum
 Luster:
Earthy (Dull)
 Streak:
white
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