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Journal Article
Published: 01 November 2023
American Mineralogist (2023) 108 (11): 1997–2003.
...William H. Peck; Dianne Keller; Victoria S. Arnold; Faith McDonald; Lily C. Kuentz; Paul M. Nugent Abstract Crushed ore in Adirondack wollastonite mines (New York) shows textural evidence for wollastonite dissolution and cementation by calcite and opal. The reaction CaSiO 3 + CO 2 = CaCO 3 + SiO 2...
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Journal Article
Published: 03 July 2023
American Mineralogist (2023) 108 (7): 1275–1288.
... characteristics of (1) low-Cs-bearing ore (amorphous silica opal-A and opal-CT type) with low Cs (average of ~0.2 wt%), Na, K, Al, and Ca contents, and (2) high-Cs-bearing ore (clay type) with high-Cs (average of ~1.40 wt%), -Na, -K, -Al, and -Ca contents. It is reported for the first time that Cs primarily...
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Journal Article
Journal: Geology
Published: 03 January 2023
Geology (2023) 51 (2): 189–192.
... of crystal growth within the gel. Over time, the gel hardened to form opal-A G . This silica phase is thermodynamically unstable and recrystallized to quartz that has a distinct mosaic texture. Mineral deposition in low-sulfidation epithermal gold deposits occurs in the shallow sub-surface, typically...
FIGURES
Journal Article
Journal: Geology
Published: 02 December 2022
Geology (2023) 51 (1): 85–90.
... interpreted to be caused by the conversion of opal-A to opal-CT ( Volpi et al., 2003 ). Figure 3. (A) Zoomed-in seismic section of slide 1. H—seismic horizon; SU—seismic unit. (B) Variance time slice calculated at ~130 ms twoway traveltime (TWT) below slide 1, revealing polygonal fault systems. (C...
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Journal Article
Published: 21 November 2022
Mineralogical Magazine (2023) 87 (2): 186–193.
..., KZnCl 3 ⋅2H 2 O, halite, sylvite, opal and gypsum. Kalithallite forms lamellar to tabular crystals up to 5 × 30 × 40 μm combined in open-work aggregates up to 1 mm across. It is transparent, colourless in individuals and white to pale cream coloured or pale beige in aggregates, with vitreous lustre. D...
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