Search results
Results from the WOW.Com Content Network
Prasiolite. Prasiolite (also known as green quartz, green amethyst or vermarine) is a green variety of quartz. Since 1950, almost all natural prasiolite has come from a small Brazilian mine, [citation needed] but it has also been mined in the Lower Silesia region of Poland. Naturally occurring prasiolite has also been found in the Thunder Bay ...
A crystal oscillator is an electronic oscillator circuit that uses a piezoelectric crystal as a frequency-selective element. [1] [2] [3] The oscillator frequency is often used to keep track of time, as in quartz wristwatches, to provide a stable clock signal for digital integrated circuits, and to stabilize frequencies for radio transmitters and receivers.
Quartz. Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO 4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO 2. Quartz is, therefore, classified structurally as a framework silicate mineral ...
In this list of presidents of the United States by age, the first table charts the age of each president of the United States at the time of presidential inauguration (first inauguration if elected to multiple and consecutive terms), upon leaving office, and at the time of death.
AOL latest headlines, entertainment, sports, articles for business, health and world news.
Rolex Datejust Oysterquartz Ref. 17014. The Rolex Oysterquartz was a quartz watch made by Rolex. Unlike most watches, The Rolex Oysterquartz features a mechanical lever escapement driven by a simple permanent magnet moving coil motor mechanically similar to a d'Arsonval galvanometer.
Heat the stock: Bring the stock to a boil. Cook the tortellini: Add the tortellini to the boiling liquid, and stir for a minute to keep the pasta separated and to prevent sticking. When the ...
Quartzite is a very hard rock composed predominantly of an interlocking mosaic of quartz crystals. The grainy, sandpaper-like surface is glassy in appearance. Minor amounts of former cementing materials, iron oxide, silica, carbonate and clay, often migrate during recrystallization, causing streaks and lenses to form within the quartzite. [1 ...