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Bakerite

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Bakerite
Bakerite sample
General
CategoryNesosilicate
Formula
(repeating unit)
Ca4B4(BO4)(SiO4)3(OH)3·H2O
Strunz classification9.AJ.20
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupP21/c
Unit cella = 4.85 Å,
b = 7.627 Å,
c = 9.659 Å; β = 90.255°; Z = 1
Identification
ColorColorless, white
Mohs scale hardness4+12
LusterVitreous, dull
DiaphaneityTranslucent
Specific gravity2.88
Optical propertiesBiaxial (-)
Refractive indexnα = 1.624 nβ = 1.635 nγ = 1.654
Birefringenceδ = 0.030
2V angleMeasured: 87° to 88°

Bakerite is the common name given to hydrated calcium boro-silicate hydroxide, a borosilicate mineral (chemical formula Ca4B4(BO4)(SiO4)3(OH)3·(H2O)) that occurs in volcanic rocks in the Baker, California area.[1] Discredited mineral: IMA2016-A.

It was first described in 1903 for an occurrence in the Corkscrew Canyon Mine of the Black Mountains, Furnace Creek District, Death Valley National Park, Inyo County, California, US.[2] It was named for Richard C. Baker, a director of the Pacific Coast Borax Company.[3][4]

References

[edit]
  1. ^ "Bakerite mineral data". WebMineral.com. Archived from the original on 5 April 2009. Retrieved 2009-05-08.
  2. ^ Mindat.org
  3. ^ Handbook of Mineralogy
  4. ^ Hildebrand, GH. (1982) Borax Pioneer: Francis Marion Smith. San Diego: Howell-North Books. p. 89. (ISBN 0-8310-7148-6)