coal-bearing layer
51Iron ore — Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in colour from dark grey, bright yellow, deep purple, to rusty red. The iron itself is usually found in the …
52Pakistan — /pak euh stan , pah keuh stahn /, n. 1. Islamic Republic of, a republic in S Asia, between India and Afghanistan: formerly part of British India; known as West Pakistan from 1947 71 to distinguish it from East Pakistan (now Bangladesh).… …
53dye — dyable, dyeable, adj. dyer, n. /duy/, n., v., dyed, dyeing. n. 1. a coloring material or matter. 2. a liquid containing coloring matter, for imparting a particular hue to cloth, paper, etc. 3. color or hue, esp. as produced by dyeing. 4. of the… …
54fungus — fungic /fun jik/, adj. funguslike, adj. /fung geuhs/, n., pl. fungi /fun juy, fung guy/, funguses, adj. n. 1. any of a diverse group of eukaryotic single celled or multinucleate organisms that live by decomposing and absorbing the organic… …
55Silicon nitride — Preferred IUPAC name Silicon nitride …
56Colombia — Colombian, adj., n. /keuh lum bee euh/; Sp. /kaw lawm byah/, n. a republic in NW South America. 37,418,290; 439,828 sq. mi. (1,139,155 sq. km). Cap.: Bogotá. * * * Colombia Introduction Colombia Background: Colombia was one of the three countries …
57South America — South American. a continent in the S part of the Western Hemisphere. 271,000,000; ab. 6,900,000 sq. mi. (17,871,000 sq. km). * * * Continent, Western Hemisphere. The world s fourth largest continent, it is bounded by the Caribbean Sea to the… …
58atmosphere, evolution of — Introduction the development of Earth s (Earth) atmosphere across geologic time. The process by which the current atmosphere arose from earlier conditions is complex; however, evidence related to the evolution of Earth s atmosphere, though… …
59iron processing — Introduction use of a smelting process to turn the ore into a form from which products can be fashioned. Included in this article also is a discussion of the mining of iron and of its preparation for smelting. Iron (Fe) is a… …
60Nigeria — Nigerian, adj., n. /nuy jear ee euh/, n. a republic in W Africa: member of the Commonwealth of Nations; formerly a British colony and protectorate. 107,129,469; 356,669 sq. mi. (923,773 sq. km). Cap.: Abuja. Official name, Federal Republic of… …
