Columbia Encyclopedia

(Encyclopedia) tanzanite tănzănˈīt [key], beautiful gemstone discovered in 1967 in the Umba Valley near the Usambara Mts. in Tanzania, a precious variety of the mineral zoisite, a calcium aluminum silicate. Zois...

(Encyclopedia) Shannon, Charles Haslewood or Hazelwood, 1865–1937, English portrait and figure painter, etcher, and lithographer. He was an aesthete and lifelong companion of fellow artist Charles Ricketts, who in...

(Encyclopedia) mullet, blunt-nosed, tropical and temperate water fishes of the family Mugilidae, found worldwide. Small schools of mullets frequent shallow waters, feeding on aquatic plants and on mud, which is grou...

(Encyclopedia) Scottish terrier, breed of short-legged terrier perfected in Scotland in the mid-19th cent. It stands about 10 in. (25 cm) high at the shoulder and weighs from 18 to 22 lb (8.2–10.0 kg). Its dense, ...

(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...

(Encyclopedia) galena gəlēˈnə [key] or lead glance, lustrous, blue-gray mineral crystallizing usually in cubes, sometimes in octahedrons. It is the most important ore and the principal source of lead. It consist...

(Encyclopedia) narwhal närˈwəl [key], a small arctic whale, Monodon monoceros. The males of the species, and an occasional female, bear a single, tightly spiraled tusk that measures up to 9 ft (2.7 m) in length. ...

(Encyclopedia) tree shrew, small, arboreal mammal of the family Tupaiidae, found in S Asia. The 17 known species of tree shrews are classified as the order Tupaioidea or Scandentia. Tree shrews superficially resembl...

(Encyclopedia) rhea rēˈə [key], common name for a South American bird of the family Rheidae, which is related to the ostrich. Weighing from 44 to 55 lb (20–25 kg) and standing up to 60 in. (152 cm) tall, the rh...

(Encyclopedia) selenium səlēˈnēəm [key], nonmetallic chemical element; symbol Se; at. no. 34; at. wt. 78.96; m.p. 217℃; b.p. about 685℃; sp. gr. 4.81 at 20℃; valence −2, +4, or +6. Selenium is directly ...