Veatchite

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Veatchite
Veatchite.jpg
Veatchite-p, Billie Mine, Death Valley, California
General
Category Phylloborates
Formula
(repeating unit)
Sr2B11O16(OH)5 · H2O
Strunz classification 6.EC.15
Crystal system Monoclinic
Crystal class Domatic (m)
(same H-M symbol)
Space group Aa
Unit cell a = 20.81 Å, b = 11.74 Å
c = 6.63 Å; β = 92.03°; Z = 8
Identification
Color Colorless to white
Crystal habit Flattened platey to prismatic crystals, diverging fibrous clusters and cross fiber veinlets
Cleavage Perfect on {010}, indistinct on {001}
Mohs scale hardness 2
Luster Vitreous to pearly
Diaphaneity Transparent to translucent
Specific gravity 2.62
Optical properties Biaxial (+)
Refractive index nα = 1.551 nβ = 1.553 nγ = 1.620
Birefringence δ = 0.069
2V angle Measured: 37°
References [1][2][3]

Veatchite is an unusual strontium borate, with the chemical formula Sr2B11O16(OH)5·H2O. There are two known polytypes, veatchite-A and veatchite-p.[4]

Veatchite was discovered in 1938, at the Sterling Borax mine in Tick Canyon, Los Angeles County, California. Veatchite is named to honor John Veatch, the first person to detect boron in the mineral waters of California.

See also[edit]

References[edit]

  1. ^ Veatchite on Mindat.org
  2. ^ Veatchite data on Webmineral
  3. ^ Veatchite in the Handbook of Mineralogy
  4. ^ Grice J D, Pring A (2012) Veatchite: structural relationships of the three polytypes, American Mineralogist 97, 489-495

External links[edit]

Media related to Veatchite at Wikimedia Commons