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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 ...
Note: first definitive work of modern mineralogy. Nicols, Thomas (1652). A Lapidary or, The History of Precious Stones: With Cautions for the Undeceiving of all those that deal with Precious Stones (1 ed.). Cambridge: printed by Thomas Buck. p. 239. Note: it was written with the help of 'de Boodt's' book. Johann Martin Michaelis (1693).
[47] [52] In December 1969, Seiko produced the world's first commercial quartz wristwatch, the Seiko Quartz-Astron 35SQ [53] [54] which is now honored with IEEE Milestone. [ 55 ] [ 56 ] The Astron had a quartz oscillator with a frequency of 8,192 Hz and was accurate to 0.2 seconds per day, 5 seconds per month, or 1 minute per year.
In 1969, Seiko produced the world's first quartz wristwatch, the Astron. [200] During the 1970s, the introduction of digital watches made using transistors and plastic parts enabled companies to reduce their work force. By the 1970s, many of those firms that maintained more complicated metalworking techniques had gone bankrupt. [201]
Most such quartz clock crystals vibrate at a frequency of 32 768 Hz. The piezoelectric properties of crystalline quartz were discovered by Jacques and Pierre Curie in 1880. [65] [66] The first crystal oscillator was invented in 1917 by Alexander M. Nicholson, after which the first quartz crystal oscillator was built by Walter G. Cady in 1921. [2]
Because the first discovery sites were in the village of Middleville and in the city of Little Falls, respectively, the crystal is also known as a Middleville diamond or a Little Falls diamond. [ 3 ] Herkimer diamonds became widely recognized after workmen discovered them in large quantities while cutting into the Mohawk River Valley dolomite ...
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Granitic rock with more than 60% quartz, which is uncommon, is classified simply as quartz-rich granitoid or, if composed almost entirely of quartz, as quartzolite. [5] [6] [7] Granite in thin section, under cross-polarized light. True granites are further classified by the percentage of their total feldspar that is alkali feldspar.