Benitoite

Benitoide, Benitoiet, Benitoit, Benitoita, Бенитоит, 藍錐礦, 베니토 아이 트, ベニト石


Commonly known      rarer (so called collectors stones)      very rare (rarities)      extremely rare (world rarities)
relatively rare organic material


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Formula: BaTiSi3O9
Mineral class: silicates
Crystal system: hexagonal
Mohs scale: 6 - 6.5
Density (g/cm3): 3.64 - 3.68
Refractive index: 1.757 - 1.804
Cleavage: poor
Colors: colorless, orange, rose, purple, blue
Luster: vitreous
Fluorescence: blue
Pleochroism: colorless - greenish-blue
Largest faceted Benitoite: 15.42 ct
Deposits: See my special page!
1st Description: 1907
Name: after the type locality in San Benito County / California / USA
History:
Discovery of Benitoite in February 1907 by prospector James M. Couch. He staked claims in the name of Roderick W. Dallas in the area of the Diablo Mountains / San Benito County, searching for cinnabar or copper ores. At a hillside he spotted an interesting outcrop of rocks, detected a human-sized cave, and stepped into it. Before his feet lay thousands of blue crystals, and even more were weathered out of the white natrolite vains in the walls: Benitoite! Some crystals were sent to a San Francisco jeweler for cutting.
Finally G.D. Louderback, professor of geology at the University of California in Berkeley, was asked for identification of the unknown stones. He identified them as a new mineral, and described it in the same year, in 1909 more detailed.
Use of dynamite to ease the mining work. Only about 1% of the benitoites "survived" these "activities".
Establishment of the "Dallas Mining Company". Erection of a mine camp.
Closure of the mine in 1912 because Dallas thought that the mine had been "pinched out."
Briefly re-opening of the mine in 1933, then the mine was leased to various individuals.
Buzz Gray and Bill Forrest leased the mine in 1967.
In 1985 Benitoite became California’s State Gemstone.
Buzz Gray and Bill Forrest purchased the mine in 1987, expanded the property, tested it, and renamed it "Benitoite Gem Mine".
AZCO Mining, Inc. leased the mine in 1997 but were not very successful despite larger investments.
Collector's Edge Minerals, Inc. purchased the mine in 2000.
Collector's Edge sold the mine to Dave Schreiner of Coalinga in 2005. Dave is under a contractual agreement that prevents him from doing any heavy mining on the property until 2015.
He is allowing people, for a fee, to dig on the property however.
Sources:
www.collectorsedge.com
www.tucsonshowguide.com
www.attawaygems.com

Benitoite

Size: 0.78 x 0.57 cm
Weight: 1.42 ct
Origin: California / USA

Photo by kind permission of © www.wsfgems.com

Benitoite Mineral

Origin: California / USA
Benitoite
Benitoite

Weight: 2.70 ct

Origin: California / USA

Photo by kind permission of © www.wsfgems.com
Benitoite Ring

Benitoite: 2.70 ct; California / USA
Diamonds: total 0.72 cts
Gold: 14K White Gold

Photo by kind permission of © www.wsfgems.com
Benitoite Ring
Benitoite Brooch "Butterfly"

Benitoites: Body: 5,96 ct; wings: 28,71 ct; eyes: orange benitoite; antennas: colorless benitoites.
San Benito County / California / USA
Size: appr. 6.4 x 5.7 cm
Gold: 18K

Photo: © Robert Weldon; image by kind permission of the owners © Bernadine Johnston and Buzz Gray
Benitoite Brooch

Benitoite

Size: 0.8 x 0.7 cm
Weight: 1.66 ct
Origin: California / USA

Photo by kind permission of © www.wsfgems.com

Benitoite

Size: 0.46 x 0.68 cm
Weight: 1.0 ct
Origin: California / USA

Photo by kind permission of © www.wsfgems.com
Benitoite Pendant

Benitoite: 1.18 ct; California / USA

Gold: 14K White Gold

Photo by kind permission of © www.wsfgems.com
Benitoite Pendant

Benitoite

Size: 0.51 x 0.42 cm
Weight: 0.46 ct
Origin: California / USA

Photo by kind permission of © www.wsfgems.com
Benitoite Pendant

Benitoite: 0.25 ct; California / USA

Gold: 14K White Gold

Photo by kind permission of © www.wsfgems.com
Benitoite Pendant

Benitoite

Weight: 0.64 ct

Origin: California / USA

Photo by kind permission of © www.americanthai.com

Benitoite

Size: 0.74 x 0.98 cm
Weight: 2.12 ct
Origin: California / USA

Photo by kind permission of © www.wsfgems.com

Benitoite

Weight: 0.05 ct

Origin: Gem Mine / San Benito County / California / USA

Photo by kind permission of © www.kqminerals.com

Benitoite Mineral / UV Light

Size: 2.4 x 2.2 x 1.8 cm

Origin: Dallas Gem Mine / San Benito County / California / USA

Photo by kind permission of © www.lucianabarbosa.com
Benitoite Mineral UV light


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