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  2. Quartz - Wikipedia

    en.wikipedia.org/wiki/Quartz

    Quartz. Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO 4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO 2. Quartz is, therefore, classified structurally as a framework silicate mineral ...

  3. Quartzite - Wikipedia

    en.wikipedia.org/wiki/Quartzite

    Quartzite is a very hard rock composed predominantly of an interlocking mosaic of quartz crystals. The grainy, sandpaper-like surface is glassy in appearance. Minor amounts of former cementing materials, iron oxide, silica, carbonate and clay, often migrate during recrystallization, causing streaks and lenses to form within the quartzite. [1 ...

  4. Flint - Wikipedia

    en.wikipedia.org/wiki/Flint

    Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, [1][2] categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone tools and start fires. Flint occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones ...

  5. What's the Difference Between Quartz and Quartzite? - AOL

    www.aol.com/whats-difference-between-quartz...

    You can go to a quartz countertop manufacturer and tell them you want something that looks like another stone, and they can engineer the quartz to look like those other materials. “Since quartz ...

  6. List of mineral tests - Wikipedia

    en.wikipedia.org/wiki/List_of_mineral_tests

    The Mohs Hardness Scale is the main scale to measure mineral hardness. Finger nail is 2.5, copper coin is 3.5, glass is 5.5 and steel is 6.5. Hardness scale is Talc is 1, Gypsum is 2, Calcite is 3, Fluorite is 4, Apatite is 5, Orthoclase Feldspar is 6, Quartz is 7, Topaz is 8, Corundum is 9 and Diamond is 10. Odor.

  7. Chert - Wikipedia

    en.wikipedia.org/wiki/Chert

    Chert (/ tʃ ɜːr t /) is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, [1] the mineral form of silicon dioxide (SiO 2). [2] Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood.

  8. Thin section - Wikipedia

    en.wikipedia.org/wiki/Thin_section

    Thin sections are prepared in order to investigate the optical properties of the minerals in the rock. This work is a part of petrology and helps to reveal the origin and evolution of the parent rock. A photograph of a rock in thin section is often referred to as a photomicrograph. Thin sections are also used in the microscopic study of bones ...

  9. Sandstone - Wikipedia

    en.wikipedia.org/wiki/Sandstone

    Typically quartz and feldspar; lithic fragments are also common. Other minerals may be found in particularly mature sandstone. Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks.