Thorneite

thorneite

housleyite

markcooperite

ottoite

Images

Formula: Pb6(Te2O10)(CO3)Cl2(H2O)
Tellurate

Crystal System: Monoclinic
Specific gravity: 6.790 calculated
Hardness: 2
Streak: Pale yellow
Colour: Lemon-yellow, yellow-orange
Luminescence: Not fluorescent under UV
Solubility: Turns opaque and dissolves slowly in hydrochloric acid
Environments

Hydrothermal environments

Thorneite was approved in 2009 but to date (September 2024) it has been reported only from the Otto Mountain.

Localities

At the type locality, Bird Nest drift, Otto Mountain, Baker, Soda Mountains, Silver Lake Mining District, San Bernardino County, California, USA, thorneite occurs as a secondary phase on fracture surfaces and in small vugs in quartz veins. It is formed from the partial oxidation of primary sulphides, such as galena, and tellurides, such as hessite, during or following brecciation of the quartz veins. Thorneite is directly associated with acanthite, cerussite, gold, hessite, iodargyrite, khinite, wulfenite, housleyite, markcooperite and ottoite.
Various other secondary minerals occur in the veins, including three other new (in 2009) secondary tellurium minerals: paratimroseite, telluroperite and timroseite.
Thorneite crystals are prismatic to bladed with elongation and striations parallel to the c-axis, and typically occur in parallel and random aggregates. It is yellow and transparent, with pale yellow streak and adamantine lustre (AM 95.10.1548-1553, HOM).
Thorneite from Bird Nest Drift - Image

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