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  2. Oldest dated rocks - Wikipedia

    en.wikipedia.org/wiki/Oldest_dated_rocks

    The oldest dated rocks formed on Earth, as an aggregate of minerals that have not been subsequently broken down by erosion or melted, are more than 4 billion years old, formed during the Hadean Eon of Earth's geological history, and mark the start of the Archean Eon, which is defined to start with the formation of the oldest intact rocks on Earth.

  3. Lapis lazuli - Wikipedia

    en.wikipedia.org/wiki/Lapis_Lazuli

    A mixture of other minerals, often including pyrite. Lapis lazuli (UK: / ˌlæpɪs ˈlæz (j) ʊli, ˈlæʒʊ -, - ˌli /; US: / ˈlæz (j) əli, ˈlæʒə -, - ˌli /), or lapis for short, is a deep-blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color.

  4. Cullinan Diamond - Wikipedia

    en.wikipedia.org/wiki/Cullinan_Diamond

    Cullinan Diamond. The Cullinan Diamond is the largest gem-quality rough diamond ever found, [2] weighing 3,106 carats (621.20 g), discovered at the Premier No.2 mine in Cullinan, South Africa, on 26 January 1905. It was named after Thomas Cullinan, the owner of the mine. In April 1905, it was put on sale in London, but despite considerable ...

  5. Jack Hills - Wikipedia

    en.wikipedia.org/wiki/Jack_Hills

    Quartz-pebble metaconglomerate (Jack Hills Quartzite), the rock type that contains Earth's oldest dated mineral grains (detrital zircon) Detrital zircons with ages greater than 4 billion years old have been found in these rocks, and a 4,404 ± 8 million year old zircon was found at Erawandoo Hill; [4] this is the oldest dated material originating on Earth; the date is in the Cryptic era of the ...

  6. Yarrabubba impact structure - Wikipedia

    en.wikipedia.org/wiki/Yarrabubba_impact_structure

    Yarrabubba impact structure. Pha. Had. The Yarrabubba impact structure is the eroded remnant of an impact crater, situated in the northern Yilgarn Craton near Yarrabubba Station between the towns of Sandstone and Meekatharra, Mid West Western Australia. [2][3] With an age of 2.229 billion years, it is the oldest known impact structure on Earth.

  7. Gemstone - Wikipedia

    en.wikipedia.org/wiki/Gemstone

    Gemstone. Group of precious and semiprecious stones—both uncut and faceted—including (clockwise from top left) diamond, uncut synthetic sapphire, ruby, uncut emerald, and amethyst crystal cluster. A gemstone (also called a fine gem, jewel, precious stone, semiprecious stone, or simply gem) is a piece of mineral crystal which, when cut or ...

  8. Amber - Wikipedia

    en.wikipedia.org/wiki/Amber

    Amber becomes abundant long after the Carboniferous, in the Early Cretaceous, [1] when it is found in association with insects. The oldest amber with arthropod inclusions comes from the Late Triassic (late Carnian c. 230 Ma) of Italy, where four microscopic (0.2–0.1 mm) mites, Triasacarus, Ampezzoa, Minyacarus and Cheirolepidoptus, and a ...

  9. Morton Gneiss - Wikipedia

    en.wikipedia.org/wiki/Morton_Gneiss

    Morton gneiss, also known as rainbow gneiss, is an Archean -age gneiss found in the Minnesota River Valley of southwestern Minnesota, United States. It is one of the oldest stones on Earth, at about 3.5 billion years old. Along with the nearby Montevideo Gneiss, it is the oldest intact continental crust rock in the United States. [1]