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stibnite

(Encyclopedia)stibnite stĭbˈnīt [key], antimony sulfide, Sb2S3, a mineral, silvery gray in color, with a metallic luster. It crystallizes in the orthorhombic system. Found in many parts of the world, it is the m...

Mother Lode

(Encyclopedia)Mother Lode, belt of gold-bearing quartz veins, central Calif., along the western foothills of the Sierra Nevada. The term is sometimes limited to a strip c.70 mi (110 km) long and from 1 to 61⁄2 mi...

Cairngorms

(Encyclopedia)Cairngorms kârngôrmzˈ, kârnˈgôrmz [key], group of mountains forming part of the Grampian Mts, in Highland, Moray, and Aberdeenshire, central Scotland, between the Dee and the upper Spey rivers; ...

soapstone

(Encyclopedia)soapstone or steatite stēˈətīt [key], metamorphic rock of which the characteristic and usually chief mineral is talc, but which also contains varying parts of chlorite, mica, tremolite, quartz, ma...

silicosis

(Encyclopedia)silicosis sĭlĭkōˈsĭs [key], occupational disease of the lungs caused by inhalation of free silica (quartz) dust over a prolonged period of time. Free silica is dispersed in the air and inhaled by...

silicate

(Encyclopedia)silicate, chemical compound containing silicon, oxygen, and one or more metals, e.g., aluminum, barium, beryllium, calcium, iron, magnesium, manganese, potassium, sodium, or zirconium. Silicates may b...

microwave oven

(Encyclopedia)microwave oven, device that uses microwaves to rapidly cook food. The microwaves cause water molecules in the food to vibrate, producing heat, which is distributed through the food by induction. A spe...

Aichi

(Encyclopedia)Aichi īˈchē [key], prefecture, 1,962 sq mi (5,082 sq km), central Honshu, Japan. Bounded on the S and W by Ise Bay, Aichi consists of a coastal plain (the Nobi Plain) a...

chalcedony

(Encyclopedia)chalcedony kălsĕdˈənē [key] [from Chalcedon], form of quartz the crystals of which are so minute that its crystalline structure cannot be seen except with the aid of a microscope. Chalcedony has ...

grinding

(Encyclopedia)grinding, process by which surface material is removed from an object, usually metal, by the abrasive action of a rotating wheel or a moving belt that contains abrasive grains. A grinding wheel can be...

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