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  2. Opal - Wikipedia

    en.wikipedia.org/wiki/Opal

    Opal occurs in significant quantity and variety in central Mexico, where mining and production first originated in the state of Querétaro. In this region the opal deposits are located mainly in the mountain ranges of three municipalities: Colón, Tequisquiapan, and Ezequiel Montes. During the 1960s through to the mid-1970s, the Querétaro ...

  3. Biogenic silica - Wikipedia

    en.wikipedia.org/wiki/Biogenic_silica

    Biogenic silica (bSi), also referred to as opal, biogenic opal, or amorphous opaline silica, forms one of the most widespread biogenic minerals. For example, microscopic particles of silica called phytoliths can be found in grasses and other plants. Silica is an amorphous metalloid oxide formed by complex inorganic polymerization processes.

  4. List of mines in Mexico - Wikipedia

    en.wikipedia.org/wiki/List_of_mines_in_Mexico

    This list of mines in Mexico is subsidiary to the list of mines article and lists working, defunct and future mines in the country and is organised by the primary mineral output. For practical purposes stone, marble and other quarries may be included in this list.

  5. Ammolite - Wikipedia

    en.wikipedia.org/wiki/Ammolite

    Ammolite is an opal-like organic gemstone found primarily along the eastern slopes of the Rocky Mountains of North America.It is commonly unearthed by natural erosion or through the process of various mining practices, within the perimeter of an ancient sea bed called the Western Interior Seaway. [2]

  6. Mexican Geological Survey - Wikipedia

    en.wikipedia.org/wiki/Mexican_Geological_Survey

    The Mexican Geological Survey originated as the Directing Committee for Mexican Mineral Resource Research, established in 1944, which published bulletins on the exploration of mineral deposits. In 1949, the organization changed its name to the National Research Institute for Mineral Resources, and in 1955 it became the Non-Renewable Natural ...

  7. Cave of the Crystals - Wikipedia

    en.wikipedia.org/wiki/Cave_of_the_Crystals

    Cave of the Crystals or Giant Crystal Cave (Spanish: Cueva de los cristales) is a cave connected to the Naica Mine at a depth of 300 metres (980 ft), in Naica, Chihuahua, Mexico. It takes the form of a chamber within the limestone host rock of the mine, and is about 109 metres (358 ft) long with a volume of 5,000 to 6,000 cubic metres (180,000 ...

  8. La Revancha mine - Wikipedia

    en.wikipedia.org/wiki/La_Revancha_mine

    The deposit that the mine is on has been used to mine gold, copper and platinum for decades, before being operated by Caracol Mining Company from 2003 until 2006 [5] to mine antimony and baryte. [6] Barite grinding mill. Caracol Mining Company sold their assets to Blackfire Exploration Mexico, [5] operated by brothers Brad and Brent Willis from ...

  9. Peñasquito Mine - Wikipedia

    en.wikipedia.org/wiki/Peñasquito_Mine

    The exploration was suspended in 1997 but resumed in 2002 when Western Silver took over. A significant polymetallic deposit was discovered in 2006 and construction of the mine began in 2007, the first concentrates were produced in October 2009, and commercial production began in 2010. [4]