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The quartz oscillator or resonator was first developed by Walter Guyton Cady in 1921. [92] [93] George Washington Pierce designed and patented quartz crystal oscillators in 1923. [94] [95] [96] The quartz clock is a familiar device using the mineral. Warren Marrison created the first quartz oscillator clock based on the work of Cady and Pierce ...
The discovery of the oldest known Earth rock, found on the Moon, was reported in January 2019 by NASA scientists. Apollo 14 astronauts returned several rocks from the Moon and, later, scientists determined that a fragment from one of the rocks, nicknamed Big Bertha , contained "a bit of Earth from about 4 billion years ago".
Note: René Haüy discovered that emeralds and beryls crystals are geometrically identical. He asked Vauquelin for a chemical analysis, and so Vauquelin found a new "earth" (beryllium oxide). Carl Wilhelm Scheele (1742 –1786), discovery of oxygen with Priestley; identification of molybdenum, tungsten, barium, hydrogen, and chlorine.
Islamic alchemists advanced the sulfur-mercury theory of metals, a theory that is first found in pseudo-Apollonius of Tyana's Sirr al-khalīqa (The Secret of Creation, c. 750–850) and in the Arabic writings attributed to Jābir ibn Ḥayyān (written c. 850–950). [8]
A study published July 24 in the journal JAMA Internal Medicine analyzed 52 cases of silicosis among workers in California who fabricate quartz countertops. Of those cases, 10 workers died and ...
In their chronology for Earth, Hazen et al. (2008) separated the changes in mineral abundance into three broad intervals: planetary accretion up to 4.55 Ga (billion years ago); reworking of Earth's crust and mantle between 4.55 Ga and 2.5 Ga; and biological influences after 2.5 Ga. [1] [12] They further divided the ages into 10 intervals, some ...
12,800 years ago, the woolly mammoth suddenly disappeared. A new piece evidence may finally explain why.
Life on Earth may have begun even earlier than biologists suspected, at a time when the solar system was still in its infancy. Earth's oldest fossils yet discovered, give hope for life on Mars ...