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jade

(Encyclopedia)jade, common name for either of two minerals used as gems. The rarer variety of jade is jadeite, a sodium aluminum silicate, NaAl(SiO3)2, usually white or green in color; the green variety is the more...

Colorado–Big Thompson project

(Encyclopedia)Colorado–Big Thompson project, constructed by the U.S. Bureau of Reclamation to divert water from the headstreams of the Colorado River to irrigate c.720,000 acres (291,400 hectares) of land in NE C...

chrysoberyl

(Encyclopedia)chrysoberyl krĭsˈəbĕrˌĭl [key] [Gr.,=golden beryl], a beryllium aluminate used as a gem. It has a vitreous luster and is transparent to translucent. The more valuable cat's-eye is a variety of c...

olivine

(Encyclopedia)olivine ŏlĭvˈēn [key], an iron-magnesium silicate mineral, (Mg,Fe)2SiO4, crystallizing in the orthorhombic system. It is a common constituent of magnesium-rich, silica-poor igneous rocks; metamorp...

Equisetophyta

(Encyclopedia)Equisetophyta ĕkˌwəsətŏfˈətə [key], small division of the plant kingdom consisting of the plants commonly called horsetails and scouring rushes. Equisetum, the only living genus in this divisi...

garnet

(Encyclopedia)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 ...

bird of paradise

(Encyclopedia)bird of paradise, common name for any of 43 species of medium- to crow-sized passerine birds of New Guinea and the adjacent islands, known for the bright plumage, elongated tail feathers called wires,...

emerald flash

(Encyclopedia)emerald flash: see green flash. ...

cover crop

(Encyclopedia)cover crop, green temporary crop grown to prevent or reduce erosion and to improve the soil by building up its organic content. Green-manure crops, which are specifically grown for their organic conte...

chloroplast

(Encyclopedia)chloroplast klōrˈəplăstˌ, klôrˈ– [key], a complex, discrete green structure, or organelle, contained in the cytoplasm of plant cells. Chloroplasts are reponsible for the green color of almost...