Search results
Results from the WOW.Com Content Network
Amethyst. Amethyst is a violet variety of quartz. The name comes from the Koine Greek αμέθυστος amethystos from α- a-, "not" and μεθύσκω ( Ancient Greek) methysko / μεθώ metho ( Modern Greek ), "intoxicate", a reference to the belief that the stone protected its owner from drunkenness. [ 1]
Mica Sheet is a versatile and durable material widely used in electrical and thermal insulation applications. It exhibits excellent electrical properties, heat resistance, and chemical stability. Technical grade sheet mica is used in electrical components, electronics, in atomic force microscopy and as window sheets.
This is a list of minerals which have Wikipedia articles. Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various species. Within a mineral species there may be variation in physical properties or minor amounts of impurities that are recognized by ...
A collection of gemstone pebbles made by tumbling the rough stones, except the ruby and tourmaline, with abrasive grit inside a rotating barrel. The largest pebble here is 40 mm (1.6 in) long. The traditional classification in the West, which goes back to the ancient Greeks, begins with a distinction between precious and semi-precious; similar ...
For example, amethyst is a purple variety of the mineral species quartz. Some mineral species can have variable proportions of two or more chemical elements that occupy equivalent positions in the mineral's structure; for example, the formula of mackinawite is given as (Fe,Ni) 9 S 8, meaning Fe x Ni 9-x S 8, where x is a variable number between ...
An uncut, rough yellow sapphire found at the Spokane Sapphire Mine near Helena, Montana. Sapphire is one of the two gem-varieties of corundum, the other being ruby (defined as corundum in a shade of red). Although blue is the best-known sapphire color, it occurs in other colors, including gray and black, and also can be colorless.
Pyrrhotite ( pyrrhos in Greek meaning "flame-coloured") is an iron sulfide mineral with the formula Fe (1-x) S (x = 0 to 0.125). It is a nonstoichiometric variant of FeS, the mineral known as troilite . Pyrrhotite is also called magnetic pyrite, because the color is similar to pyrite and it is weakly magnetic.
Copper. face-centered cubic (fcc) ( cF4) Copper is a chemical element; it has symbol Cu (from Latin cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and ...