For the community in California formerly named Colemanite, see Ryan, California.
Colemanite
General
Category
Inoborates
Formula (repeating unit)
Ca2B6O11·5H2O
IMA symbol
Cole[1]
Strunz classification
6.CB.10
Crystal system
Monoclinic
Crystal class
Prismatic (2/m) (same H-M symbol)
Space group
P21/a
Unit cell
a = 8.712(2) Å, b = 11.247(3) Å, c = 6.091(1) Å; β = 110.12°; Z = 4
Identification
Color
Colorless, white, yellowish, grey
Crystal habit
Massive granular to coarsely crystalline, most commonly nodular.
Cleavage
[010] perfect, [001] distinct
Fracture
Brittle uneven to subconchoidal
Mohs scale hardness
4.5
Luster
Vitreous
Streak
White
Diaphaneity
Transparent to translucent
Specific gravity
2.42
Optical properties
Biaxial (+)
Refractive index
nα = 1.586 nβ = 1.592 nγ = 1.614
Birefringence
δ = 0.028
Fusibility
1.5
Diagnostic features
Exfoliates on heating, produces a green flame
Other characteristics
Bright pale yellow fluorescence, may phosphoresce pale green; pyroelectric and piezoelectric at very low temperature.
References
[2][3][4][5][6]
Colemanite (Ca2B6O11·5H2O)[6] or (CaB3O4(OH)3·H2O)[4] is a borate mineral found in evaporite deposits of alkaline lacustrine environments. Colemanite is a secondary mineral that forms by alteration of borax and ulexite.[3]
It was first described in 1884 for an occurrence near Furnace Creek in Death Valley and was named after William Tell Coleman (1824–1893), owner of the mine "Harmony Borax Works" where it was first found.[4] At the time, Coleman had alternatively proposed the name "smithite" instead after his business associate Francis Marion Smith.[7]
^Schorn, Stefan; et al. (2021). "Colemanit (Colemanite)". Mineralienatlas.
^ abKlein, Cornelis; Hurlbut, Cornelius S. Jr. (1993). Manual of mineralogy: (after James D. Dana) (21st ed.). New York: Wiley. p. 422. ISBN 0-471-57452-X.
^ abcColemanite, Mindat.org, retrieved 30 December 2021
^"Colemanite mineral data". Webmineral. Retrieved 30 December 2021.
^ abAnthony, John W.; Bideaux, Richard A.; Bladh, Kenneth W.; Nichols, Monte C. (2005). "Colemanite" (PDF). Handbook of Mineralogy.
^Hildebrand, GH. (1982) Borax Pioneer: Francis Marion Smith. San Diego: Howell-North Books. p 31 ISBN 0-8310-7148-6
Colemanite (Ca2B6O11·5H2O) or (CaB3O4(OH)3·H2O) is a borate mineral found in evaporite deposits of alkaline lacustrine environments. Colemanite is a secondary...
[B(O,OH)4]− anion exists as well. Many borate minerals, such as borax, colemanite, and ulexite, are salts: soft, readily soluble, and found in evaporite...
to gradually melt the silica sand, limestone, kaolin clay, fluorspar, colemanite, dolomite and other minerals until a liquid forms. It is then extruded...
tuft of acicular crystals. Ulexite is frequently found associated with colemanite, borax, meyerhofferite, hydroboracite, probertite, glauberite, trona,...
precipitate is calcium borate. A hydrated form occurs naturally as the minerals colemanite, nobleite and priceite.[citation needed] One of its uses is as a binder...
borosilicate minerals such as borax, boracite, ulexite (boronatrocalcite) and colemanite. Borates also occur in seawater, where they make an important contribution...
sphalerite (ZnS), an ore of zinc; cassiterite (SnO2), an ore of tin; and colemanite, an ore of boron. Gems are minerals with an ornamental value, and are...
and ores, however: the main source is borax, but it is also found in colemanite, boracite, kernite, tusionite, berborite and fluoborite. Major world miners...
of what he believed to be gypsum. Further testing revealed it was the colemanite form of borax. Francis Marion "Borax" Smith bought the claim for his Pacific...
Crater on Mars. Economically important sources of boron are the minerals colemanite, rasorite (kernite), ulexite and tincal. Together these constitute 90%...
Borax Works in Death Valley ceased with the development of the richer Colemanite borax deposits at Borate in the Calico Mountains, which were discovered...
Activity at Harmony Borax Works ceased with the development of the richer Colemanite borax deposits at Borate in the Calico Mountains, where they continued...
Coleman died at his home in San Francisco on November 22, 1893. The mineral Colemanite was named in his honor. The actor Gregg Palmer was cast as Coleman in...
(RGRK). They produce zinc and lead concentrates as well as boric acid colemanite. The Soviet planned economy aimed to establish industrial facilities in...
mixtures of formaldehyde, glyceraldehyde, and borate minerals such as colemanite (Ca2B6O115H2O) or kernite (Na2B4O7). However, issues remain with both...
of one to two weeks. A mortar is made with a "flux" (glass, soda, or colemanite) to help fuse it. The adobe blocks are laid so that the joints are staggered...
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