enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Gypsum - Wikipedia

    en.wikipedia.org/wiki/Gypsum

    This form of gypsum is contaminated by impurities found in the rock, namely fluoride, silica, radioactive elements such as radium, and heavy metal elements such as cadmium. [31] Similarly, production of titanium dioxide produces titanium gypsum (TG) due to neutralization of excess acid with lime. The product is contaminated with silica ...

  3. Selenite (mineral) - Wikipedia

    en.wikipedia.org/wiki/Selenite_(mineral)

    Selenite, satin spar, desert rose, and gypsum flower are crystal habit varieties of the mineral gypsum.. All varieties of gypsum, including selenite and alabaster, are composed of calcium sulfate dihydrate (meaning that it has two molecules of water), with the chemical formula CaSO 4 ·2H 2 O. Selenite contains no selenium, the similar names both derive from Greek selḗnē (σελήνη 'Moon').

  4. Alabaster - Wikipedia

    en.wikipedia.org/wiki/Alabaster

    Black alabaster is a rare anhydrite form of the gypsum-based mineral. The black form is found in only three veins in the world, one each in United States, Italy, and China. Alabaster Caverns State Park, near Freedom, Oklahoma, is home to a natural gypsum cave in which much of the gypsum is in the form of alabaster. There are several types of ...

  5. Alabaster Caverns State Park - Wikipedia

    en.wikipedia.org/wiki/Alabaster_Caverns_State_Park

    The gypsum is mostly in the form of alabaster. There are several types of alabaster found at the site, including pink, white, and the rare black alabaster. This black alabaster can be found in only three veins in the world, one each in Oklahoma, Italy and China. Another form of gypsum can be found in the many selenite crystal formations. [4]

  6. List of minerals of Pakistan - Wikipedia

    en.wikipedia.org/wiki/List_of_minerals_of_Pakistan

    Dina, Jhelum District have been reported to be the best places where economic deposits of bentonite are found. [2] Mansehra: Calcite: In Punjab, deposits are found in the cracks of limestone in the form of veins. It is found in Attock, Rawalpindi, Chakwal, Jhelum, and D.G. Khan Districts.

  7. Phosphogypsum - Wikipedia

    en.wikipedia.org/wiki/Phosphogypsum

    Phosphogypsum (PG) is the calcium sulfate hydrate formed as a by-product of the production of fertilizer, particularly phosphoric acid, from phosphate rock. It is mainly composed of gypsum (CaSO 4 ·2H 2 O).

  8. Desert rose (crystal) - Wikipedia

    en.wikipedia.org/wiki/Desert_rose_(crystal)

    Saharan gypsum desert rose from Tunisia (length 47 cm) Baryte rose from Cleveland County, Oklahoma (size: 10.2 × 7.1 × 5.5 cm) Large desert rose formation in the Tunisian desert A desert rose is an intricate rose -like formation of crystal clusters of gypsum or baryte , which include abundant sand grains. [ 1 ]

  9. Caliche - Wikipedia

    en.wikipedia.org/wiki/Caliche

    Caliche can also form on outcrops of porous rocks or in rock fissures where water is trapped and evaporates. [8] In general, caliche deposition is a slow process, requiring several thousand years. [3] The depth of the caliche layer is sensitive to mean annual rainfall.