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Properties of the Elements and Inorganic Compounds
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Name Polymidite Portlandite Powellite Protoenstatite Proustite Pseudowollastonite Pyrargyrite Pyrite Pyrolusite Pyrope Pyrophyllite Pyroxmangite Pyrrhotite Quartz () Quartz () Rammelsbergite Realgar Retgersite Riebeckite Rutile Safflorite Fe-Sanidine Sanmartinite Sapphirine Schorl Selenium (gray) Sellaite Senarmontite Shandite Shortite Siderite Silicon Sillimanite Silver Silver telluride I Silver telluride II Fe-Skutterudite Ni-Skutterudite Smithsonite Sodium melilite Sperrylite Spessartite Sphalerite Sphene Spinel Spodumene Spodumene () Staurolite Sternbergite Stibnite Stilleite Stishovite Stolzite Stromeyerite Sulfur (monoclinic) Sulfur (rhombohedral) Formula Crystal system cubic hexagonal tetragonal orthorhombic rhombohedral triclinic rhombohedral cubic tetragonal cubic monoclinic triclinic hexagonal hexagonal hexagonal orthorhombic monoclinic tetragonal monoclinic tetragonal orthorhombic monoclinic monoclinic monoclinic rhombohedral hexagonal tetragonal cubic rhombohedral orthorhombic rhombohedral cubic orthorhombic cubic cubic cubic cubic cubic rhombohedral tetragonal cubic cubic cubic monoclinic cubic monoclinic tetragonal monoclinic orthorhombic orthorhombic cubic tetragonal tetragonal orthorhombic monoclinic rhombohedral Structure type spinel cadmium iodide scheelite Z a/Å 9.480 3.5933 5.226 9.25 10.816 6.90 11.052 5.4175 4.388 11.459 5.14 7.56 3.440 4.9136 4.999 4.757 9.29 6.782 9.729 4.5937 5.231 8.689 4.691 9.96 16.032 4.3642 4.621 11.152 5.576 4.961 4.6887 5.4305 7.4843 4.0862 5.29 6.585 8.1814 8.3300 4.6528 8.511 5.968 11.621 5.4093 7.07 8.080 9.451 7.5332 7.90 11.60 11.229 5.6685 4.1790 5.4616 4.066 11.04 10.818
General geology
Published in M.L. Jeremic, Rock Mechanics in Salt Mining, 2020
In North America the main concentration of sodium salt facies is in Wyoming, where large deposits of trona were sedimented. During the Eocene period a large body of water called Lake Gosiute (the modern Green River basin) underwent many stages of filling and drying with associated deposition of sodium salts. This precipitation of the evaporite minerals could only have occurred in the presence of considerable amounts of carbon dioxide, which must have been provided in the lake by decaying plants and animals.14 The sodium salt-bearing strata belong to the Green River formation, which consists of lacustrine, claystone, siltstone, malstone and a few interbeds of buff limestone, dolomite, and sandstone. Wilkins peak member contains the saline facies, which formed when the lake shrank to about 1/3 of its original length (Figure 1.4.3). The Wilkins member occurs as a large lenses surrounded by the fluvial sediments of the Wasatch formation. The main body of the salt deposit consists of trona mixed with halite. The beds of the trona deposits frequently contain the mineral shortite. The Wilkins peak member is an evaporite-bearing unit sandwiched between the Laney member on the top and the Tipton member – Luman member on the bottom. The Laney member starts with light grey or white dolomitic marlstone and chippy shale to chalky buff laminated and varved limestone. The base of the Laney member is easy to recognize since oil shale occurs as a prominent marker. The Wilkins member itself is characterised by the abundance of dolomite and saline minerals. The member is thick, between 285 and 370 m and consists of more than 42 seams of trona, or mixed halite and trona. The trona beds which are economic are 1–12 m thick (25 beds).15
Carbonatites: related ore deposits, resources, footprint, and exploration methods
Published in Applied Earth Science, 2018
George J. Simandl, Suzanne Paradis
Carbonatites with mineralogy similar to Ol Doinyo Lengai natrocarbonatite may have been relatively common in Earth's history; however, because they convert rapidly into calcite carbonatites in the near surface environment (Zaitsev and Keller 2006), they are not preserved in the geological record. Destruction of nyerereite (the main natrocarbonatite-forming mineral) in surface environments takes place over a few months or less according to the following alteration sequence: nyerereite → pirssonite → calcite → shortite (Zaitsev et al. 2008).