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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.
Earth is the only place in the universe known to harbor life, where it exists in myriad environments. [8] [9] The origin of life on Earth was at least 3.5 billion years ago, possibly as early as 3.8-4.1 billion years ago. [2] [3] [4] Since its emergence, life has persisted in several geological environments.
Hadean zircon is the oldest-surviving crustal material from the Earth's earliest geological time period, the Hadean eon, about 4 billion years ago. Zircon is a mineral that is commonly used for radiometric dating because it is highly resistant to chemical changes and appears in the form of small crystals or grains in most igneous and metamorphic host rocks.
"In addition, the fact that these chemical building blocks of life can be formed in space and are widespread throughout the solar system increases the chances that life could have started beyond ...
Taaffeite (/ ˈ t ɑː f aɪ t /; BeMgAl 4 O 8) is a mineral, named after its discoverer Richard Taaffe (1898–1967) who found the first sample, a cut and polished gem, in October 1945 in a jeweler's shop in Dublin, Ireland. [4] [5] As such, it is the only gemstone to have
Lapis lazuli (UK: / ˌ l æ p ɪ s ˈ l æ z (j) ʊ l i, ˈ l æ ʒ ʊ-,-ˌ l i /; US: / ˈ l æ z (j) ə l i, ˈ l æ ʒ ə-,-ˌ l i /), 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.
The Genesis Rock (sample 15415) is a sample of Moon rock retrieved by Apollo 15 astronauts James Irwin and David Scott in 1971 during the second lunar EVA, at Spur crater on Earth's Moon. With a mass of c. 270 grams (4,200 grains), [ 1 ] it is currently stored at the Lunar Sample Laboratory Facility in Houston, Texas .
Hibonite is a mineral with the chemical formula (Ca,Ce)(Al,Ti,Mg) 12 O 19, occurring in various colours, with a hardness of 7.5–8.0 and a hexagonal crystal structure. It is rare, but is found in high-grade metamorphic rocks on Madagascar. Some presolar grains in primitive meteorites consist of hibonite.