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  2. Quartz - Wikipedia

    en.wikipedia.org/wiki/Quartz

    Quartz is, therefore, classified structurally as a framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. [9] Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation ...

  3. Zunyite - Wikipedia

    en.wikipedia.org/wiki/Zunyite

    Glassy, translucent, gray-tan, pseudohexagonal zunyite crystals on a milky quartz matrix. From the Big Bertha Mine, Dome Rock Mountains , La Paz County, Arizona (size: 3.3 x 3.2 x 2.8 cm)) Zunyite occurs in highly aluminous shales and hydrothermally altered volcanic rocks .

  4. History of mineralogy - Wikipedia

    en.wikipedia.org/wiki/History_of_mineralogy

    The 23rd edition is now in print under the title Manual of Mineral Science (Manual of Mineralogy) (2007), revised by Cornelis Klein and Barbara Dutrow. Equally influential was Dana's System of Mineralogy, first published in 1837, which has consistently been updated and revised. The 6th edition (1892) [27] being edited by his son Edward ...

  5. Planar deformation features - Wikipedia

    en.wikipedia.org/wiki/Planar_deformation_features

    Planar deformation features in quartz identify it as shocked quartz. Planar deformation features, or PDFs, are optically recognizable microscopic features in grains of silicate minerals (usually quartz or feldspar), consisting of very narrow planes of glassy material arranged in parallel sets that have distinct orientations with respect to the grain's crystal structure.

  6. Timeline of the discovery and classification of minerals

    en.wikipedia.org/wiki/Timeline_of_the_discovery...

    Georgius Agricola is considered the 'father of mineralogy'. Nicolas Steno founded the stratigraphy (the study of rock layers (strata) and layering (stratification)), the geology characterizes the rocks in each layer and the mineralogy characterizes the minerals in each rock.

  7. Charnockite - Wikipedia

    en.wikipedia.org/wiki/Charnockite

    Late-stage charnockite dykes cutting anorthosite, Rogaland, Norway Job Charnock's Mausoleum at St John's Church compound, Kolkata. Charnockite (/ ˈ tʃ ɑːr n ə k aɪ t /) is any orthopyroxene-bearing quartz-feldspar rock formed at high temperature and pressure, commonly found in granulite facies’ metamorphic regions, sensu stricto as an endmember of the charnockite series.

  8. Luminescence dating - Wikipedia

    en.wikipedia.org/wiki/Luminescence_dating

    The natural minerals that are measured are usually either quartz or potassium feldspar sand-sized grains, or unseparated silt-sized grains. There are advantages and disadvantages to using each. For quartz, blue or green excitation wavelengths are normally used and the near ultra-violet emission is measured (Anti- Stokes shift ).

  9. Euhedral and anhedral - Wikipedia

    en.wikipedia.org/wiki/Euhedral_and_anhedral

    As a halite crystal is growing, new atoms can very easily attach to the parts of the surface with rough atomic-scale structure and many dangling bonds.Therefore, these parts of the crystal grow out very quickly (yellow arrows).