garnet, name applied to a group of isomorphic minerals crystallizing in the cubic system. They are used chiefly as gems and as abrasives (as in garnet paper). The garnets are double silicates; one of the metallic elements is calcium, magnesium, ferrous iron, or manganese and the other aluminum, ferric iron, or chromium. Six varieties (of which there are also intermediate forms) are distinguished according to composition—grossularite (calcium-aluminum), pyrope (magnesium-aluminum), spessartite (manganese-aluminum), almandite (iron-aluminum), andradite (calcium-iron), and uvarovite (calcium-chromium). Grossularite occurs commonly in a red, green, yellow, or brown shade, depending on the impurities; if pure it would be colorless. The yellow and brown stones, coming chiefly from Sri Lanka, are used as gems under the names essonite (or hessonite) and cinnamon stone; sometimes they are miscalled hyacinth. Grossularite is found also in the Transvaal, in Mexico, and in Oregon. The most popular variety of garnet is the ruby-red pyrope from Bohemia, S Africa, and Arizona, sold as Cape ruby and Arizona ruby. Rhodolite, a mixture of pyrope and almandite from North Carolina, is rose-red or purple. Spessartite, a brown to brownish-red garnet from Bavaria, Sri Lanka, and parts of the United States, is seldom used for jewelry. Deep red, transparent almandite is the carbuncle; it was formerly a very popular gem. Almandites come chiefly from Brazil, India, and Sri Lanka; Australia and parts of the United States are also important sources. Andradite, a very common variety, is usually some shade of red, black, brown, yellow, or green. Gem varieties include topazolite, similar in color and transparency to topaz; demantoid, a green variety with a high dispersion and adamantine luster, sometimes miscalled olivine and Uralian emerald; and black melanite. Demantoid is found in the Urals, and the other andradites come chiefly from Europe and the United States. Uvarovite, an emerald-green variety from Russia and Finland, is rarely suitable for gem use. Garnet occurs in many different kinds of rocks—grossularite, in metamorphosed impure limestones; pyrope, in basic igneous rocks; spessartite, in granite rocks; almandite, in schists and other metamorphic rocks as well as in igneous rocks; andradite, in serpentine; and uvarovite, chiefly in serpentine.

Wolseley, Garnet Joseph Wolseley, 1st Viscount, 1833-1913, British field marshal. He fought in Burma (present-day Myanmar; 1852-53), the Crimea (1854-56), India (1857-58), and China (1860), and was an observer in the American Civil War. Later he went to Canada as commander of the Red River expedition (1870), and suppressed the rebellion led by Louis Riel at Fort Garry. After conducting the Ashanti campaign (1873-74), he served as high commissioner of Cyprus (1878) and as an administrator in South Africa (1879-80). His most famous achievements were the brilliant defeat of Arabi Pasha, leader of an Egyptian army revolt, at Tell el Kebir in 1882 and his attempt to relieve General Charles G. Gordon at Khartoum (1884-85), for which he was made a viscount. A tireless advocate of army reform, he became (1871) assistant adjutant general at the war office and worked with Viscount Cardwell to achieve shorter periods of enlistment, abolition of the purchase of commissions, and the creation of an army reserve. As quartermaster general (1880-82), adjutant general (1882-90), commander in chief for Ireland (1890-95), and commander in chief of the army (1895-1901), he continued to press for reform and was responsible for the modernization of training and equipment. He wrote The Story of a Soldier's Life (1903).

Garnet, Henry Highland, 1815-82, American abolitionist clergyman, b. Kent co., Md. Born a slave, he escaped in 1824 and was educated at the Oneida Institute, Whitesboro, N.Y. He was an eloquent speaker, but his radicalism, particularly in a speech at Buffalo in 1843, in which he called upon slaves to rise and slay their masters, caused his influence to decline. He was opposed and superseded in leadership by the more moderate Frederick Douglass. Garnet served as a Presbyterian pastor in Troy, N.Y., in New York City, and in Washington, D.C. In 1881 he was appointed minister to Liberia, but he died two months after his arrival there.

Garnet, Henry: see Garnett, Henry.

Any of a group of common silicate minerals with identical crystal structure but highly variable chemical composition. Garnets are most often found in metamorphic rocks but also occur in certain types of igneous rocks, and, usually in minor amounts, in some sedimentary rocks. They may be colourless, black, or many shades of red and green. Garnets are hard, and they fracture with sharp edges. They are used as abrasives for fine sanding and polishing of wood, leather, glass, metals, and plastics, as sandblasting agents, and in nonskid surface coatings. Garnet is the birthstone for January. Garnets have been mined in New York, Maine, and Idaho in the U.S., the world's leading producer; notable quantities have also been found in Australia, China, India, and elsewhere.

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(born 1815, New Market, Md., U.S.—died Feb. 13, 1882, Liberia) U.S. clergyman and abolitionist. Born a slave, he escaped in 1824 to New York, where he became a Presbyterian minister. He joined the American Anti-Slavery Society and agitated for emancipation; in a 1843 speech at a national convention of freedmen he called on slaves to revolt and murder their masters. The convention refused to endorse his radicalism, and he gradually turned more toward religion, serving as pastor in a number of Presbyterian pulpits during the next two decades. Late in life he favoured emigration of U.S. blacks to Africa. He was appointed U.S. minister to Liberia in 1881 but died within two months of his arrival in the African nation.

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(born 1815, New Market, Md., U.S.—died Feb. 13, 1882, Liberia) U.S. clergyman and abolitionist. Born a slave, he escaped in 1824 to New York, where he became a Presbyterian minister. He joined the American Anti-Slavery Society and agitated for emancipation; in a 1843 speech at a national convention of freedmen he called on slaves to revolt and murder their masters. The convention refused to endorse his radicalism, and he gradually turned more toward religion, serving as pastor in a number of Presbyterian pulpits during the next two decades. Late in life he favoured emigration of U.S. blacks to Africa. He was appointed U.S. minister to Liberia in 1881 but died within two months of his arrival in the African nation.

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