Geological - Fossils and Minerals

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Geological Benitoite Crystals with Neptunite on Nartolite 027069

Rare Geological 'Benitoite Crystals with Neptunite' on Nartolite
Benitoite, 354 grams, 12 cm. Fine crystals of neptunite (black) and benitoite (blue) on natrolite, from the classic California, USA, locality, benitoite (ben-EE-toe-ite) is a rare blue barium titanium silicate mineral, found in hydrothermally altered serpentinite. Benitoite fluoresces under short wave ultraviolet light, appearing bright blue to bluish white in color. The more rarely seen clear to white benitoite crystals fluoresce red under long-wave UV light. It was first described in 1907 by George D. Louderback, who named it benitoite for its occurrence near the headwaters of the San Benito River in San Benito County, California. Very fine condition, Rare. Provenance: ex Douglas Rose collection; formerly in the Christopher Cavey collection.
£450.00

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Geological Benitoite Crystals with Neptunite on Nartolite 027069
Geological ‘Aquamarine Crystals’ on Matrix 027070

Rare Geological 'Aquamarine Crystals' on Matrix
1kg, 13 cm. A number of fine single and parallel twinned aquamarine crystals on matrix with accessory albite, muscovite, and an acicular mineral, probably goethite, from Afghanistan. The specimen has at least 14 individual and parallel twinned crystals; the largest crystal and several of the smaller crystals contain inclusions of the acicular mineral, identified as goethite. Aquamarine is one of the gemstone varities of the mineral beryl, a beryllium aluminium silicate. Unusually very fine specimen. Provenance: ex Douglas Rose collection; formerly with Gregory, Botley and Lloyd of London (with a copy of the original invoice dated 28th November 1996 for £425.00).
£450.00

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Geological ‘Aquamarine Crystals’ on Matrix 027070


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