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  2. List of minerals - Wikipedia

    en.wikipedia.org/wiki/List_of_minerals

    This is a list of minerals which have Wikipedia articles. Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various species .

  3. Rare-earth mineral - Wikipedia

    en.wikipedia.org/wiki/Rare-earth_mineral

    Rare-earth ore, shown with a United States penny for size comparison. A rare-earth mineral contains one or more rare-earth elements as major metal constituents. Rare-earth minerals are usually found in association with alkaline to peralkaline igneous complexes in pegmatites. This would be associated with alkaline magmas or with carbonatite ...

  4. Rare-earth element - Wikipedia

    en.wikipedia.org/wiki/Rare-earth_element

    Though rare-earth elements are technically relatively plentiful in the entire Earth's crust (cerium being the 25th-most-abundant element at 68 parts per million, more abundant than copper), in practice this is spread thin across trace impurities, so to obtain rare earths at usable purity requires processing enormous amounts of raw ore at great ...

  5. Ore - Wikipedia

    en.wikipedia.org/wiki/Ore

    Iron ore (banded iron formation) Manganese ore – psilomelane (size: 6.7 × 5.8 × 5.1 cm) Lead ore – galena and anglesite (size: 4.8 × 4.0 × 3.0 cm). Ore is natural rock or sediment that contains one or more valuable minerals, typically including metals, concentrated above background levels, and that is economically viable to mine and process.

  6. Commonly used gamma-emitting isotopes - Wikipedia

    en.wikipedia.org/wiki/Commonly_used_gamma...

    A rare but notable gamma source is sodium-24; this has a fairly short half-life of 15 hours, but it emits photons with very high energies (>2 MeV). It could be used for radiography of thick steel objects if the radiography occurred close to the point of production.

  7. Wikipedia : WikiProject Rocks and minerals/Worklist

    en.wikipedia.org/wiki/Wikipedia:WikiProject...

    This is a list of the various minerals, mineraloids, and varieties that are in Wikipedia. The list is split into 3 sections - those done up top, those to do below, and minerals without wiki articles last. Note that this list was generated from List of minerals, so any omissions here ought to be corrected there too.

  8. List of gemstones by species - Wikipedia

    en.wikipedia.org/wiki/List_of_gemstones_by_species

    Main menu. Main menu. move to sidebar hide. Navigation ... Download QR code; Print/export ... This is a list of gemstones, ...

  9. Iron ochre - Wikipedia

    en.wikipedia.org/wiki/Iron_ochre

    Iron ochre or iron ocher (Ancient Greek: ὠχρός, pale yellow, orange) refers to at least three iron ore minerals, [1]: 134 common abrasives and pigments with a red-brown or brown-orange hue and the powdery consistency of ocher, were known under such a trivial name. The term “iron ocher” was primarily used among mineral collectors ...