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dolomite

(Encyclopedia)dolomite dōˈləmītˌ, dŏlˈə– [key]. 1 Mineral, calcium magnesium carbonate, CaMg (CO3)2. It is commonly crystalline and is white, gray, brown, or reddish in color with a vitreous to pearly lus...

Penderecki, Krzysztof

(Encyclopedia)Penderecki, Krzysztof kshĭshˈtôf pändĕrĕtsˈkē [key], 1933–2020, Polish composer. His music is characterized by unusual sonorities, and he devised his own system of notation to convey the eff...

Beloit

(Encyclopedia)Beloit bəˈloit [key], city (2020 pop. 36,657), Rock co., S Wis., on the Rock River; inc. 18...

blasting

(Encyclopedia)blasting, shattering, breaking, or splitting of rock or other material by the discharge of an explosive placed within or in contact with it. It is a necessary part of many engineering operations. An a...

Sela

(Encyclopedia)Sela or Selah sēˈlə [key] [Heb.,=rock], in the Bible, unidentified town, S of the Dead Sea. Amaziah captured it and renamed it Joktheel. Some identify Sela with Petra. Sela in the first chapter of ...

shaft sinking

(Encyclopedia)shaft sinking, excavation from the surface of an opening in the earth. Shafts, which are generally vertical, are usually distinguished from tunnels, which are horizontal. Little difficulty is experien...

kettle

(Encyclopedia)kettle, oval depression found in glacial moraines, which are landforms made up of rock debris. When a glacier melts and draws away from an area, a block of ice may break off and be covered by earth an...

gravel

(Encyclopedia)gravel, particles of rock, i.e., stones and pebbles, usually round in form and intermediate in size between sand grains and boulders. Gravel is composed of various kinds of rock, the most common const...

conglomerate, in geology

(Encyclopedia)conglomerate, in geology, sedimentary rock composed largely of pebbles or other rounded particles whose diameter is larger than 2 mm (.08 in.). Essentially a cemented gravel, conglomerates are formed ...

cleavage

(Encyclopedia)cleavage, tendency of many minerals to split along definite smooth planar surfaces determined by their crystal structure. The directions of these surfaces are related to weaknesses in the atomic struc...