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  2. Ore genesis - Wikipedia

    en.wikipedia.org/wiki/Ore_genesis

    High-grade gold ore from the Harvard Mine, Jamestown, California, a wide quartz-gold vein in California's Mother Lode. Specimen is 3.2 cm (1.3 in) wide. Various theories of ore genesis explain how the various types of mineral deposits form within Earth's crust. Ore-genesis theories vary depending on the mineral or commodity examined.

  3. Orogenic gold deposit - Wikipedia

    en.wikipedia.org/wiki/Orogenic_gold_deposit

    Orogenic gold deposits were only formed in certain time slices of the Earth's history. [ 7 ] [ 8 ] Orogenic gold deposits are mainly concentrated in three epochs of Earth history: (1) Neoarchean 2.8–2.5 Ga, (2) Paleoproterozoic 2.1–1.8 Ga and, (3) Phanerozoic 0.500–0.05 Ga.

  4. Mineral evolution - Wikipedia

    en.wikipedia.org/wiki/Mineral_evolution

    Most minerals on Earth formed after photosynthesis by cyanobacteria (pictured) began adding oxygen to the atmosphere. Mineral evolution is a recent hypothesis that provides historical context to mineralogy. It postulates that mineralogy on planets and moons becomes increasingly complex as a result of changes in the physical, chemical and ...

  5. Geologic temperature record - Wikipedia

    en.wikipedia.org/wiki/Geologic_temperature_record

    The geologic temperature record are changes in Earth's environment as determined from geologic evidence on multi-million to billion (10 9) year time scales. The study of past temperatures provides an important paleoenvironmental insight because it is a component of the climate and oceanography of the time.

  6. Gold mining - Wikipedia

    en.wikipedia.org/wiki/Gold_mining

    Official estimates indicate that total world gold production since the beginning of civilization has been around 6,352,216,000 troy ounces (197,576.0 t) and total gold production in Nevada is 1.1% of that, ranking Nevada as one of the Earth's primary gold-producing regions. [34] [35]

  7. Earth’s record high temperature maintained for second day - AOL

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  8. Gold Price Forecast: Gold Must Hold $1750 or Risk a Larger ...

    www.aol.com/news/gold-price-forecast-gold-must...

    Gold is consolidating after its post-Fed collapse. Prices formed a bullish engulfing candle yesterday but need to close above $1800 to support a possible bottom. A continue breakdown below $1750 ...

  9. Gold Price Prediction – Prices Formed Doji Day Following ...

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