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fertilizer

(Encyclopedia)fertilizer, organic or inorganic material containing one or more of the nutrients—mainly nitrogen, phosphorus, and potassium, and other essential elements required for plant growth. Added to the soi...

diamond

(Encyclopedia)diamond, mineral, one of two crystalline forms of the element carbon (see allotropy), the hardest natural substance known, used as a gem and in industry. The discoveries of 1870–71 in South Africa...

ammonium sulfate

(Encyclopedia)ammonium sulfate, chemical compound, (NH4)2SO4, a colorless-to-gray, rhombohedral crystalline substance that occurs in nature as the mineral mascagnite. It is soluble in water and insoluble in alcohol...

Fifty-four forty or fight

(Encyclopedia)Fifty-four forty or fight, in U.S. history, phrase commonly used by extremists in the controversy with Great Britain over the Oregon country. The rights of the United States, they maintained, extended...

Killarney

(Encyclopedia)Killarney, town (1991 pop. 7,274), Co. Kerry, SW Republic of Ireland. The town, which has mineral-water bottling, footwear, lace, hosiery, woolens, and ornamental ironwork industries, is also a touris...

fuller's earth

(Encyclopedia)fuller's earth, mineral substance characterized by the property of absorbing basic colors and removing them from oils. It is composed mainly of alumina, silica, iron oxides, lime, magnesia, and water,...

candle, cylinder of wax or tallow

(Encyclopedia)candle, cylinder of wax or tallow containing a wick, used for illumination or for ceremonial purposes. The evidence of ancient writings is not conclusive as to the history of the candle; words transla...

alloy

(Encyclopedia)alloy ălˈoi, əloiˈ [key] [O. Fr.,=combine], substance with metallic properties that consists of a metal fused with one or more metals or nonmetals. Alloys may be a homogeneous solid solution, a he...

podzol

(Encyclopedia)podzol pŏdˈsŏl [key] or podzolic soil, member of a group of soils that are gray in color, have an ashy appearance, and extend immediately south of the tundra regions of the Northern Hemisphere. Alt...

rosin

(Encyclopedia)rosin or colophony, hard, brittle, translucent resin, obtained as a solid residue from crude turpentine. Usually pale yellow or amber, its color may vary from brownish-black to transparent depending o...