Vitreous

Vitreous

Vitreous refers to a material in an amorphous, glassy state (in contrast to a crystalline state). In such a state, the constituent atoms do not exhibit the long-range order that is characteristic of crystals. However, they still exhibit short-range order -- the separation of atoms and/or the lengths of covalent bonds are very close to their typical equilibrium distances. The creation of a vitreous material by supercooling or by addition of additives prior to cooling is called vitrification.

Under certain conditions, vitreous materials may begin to rearrange themselves into crystals. This process is referred to as devitrification. Natural volcanic glass, obsidian, will de-vitrify or crystallize over extended periods of geologic time. Devitrification can also occur in glass items that are regularly washed in dishwashers due to the chemicals involved in their detergents. [ [http://www.newi.ac.uk/buckleyc/materials.htm#Glass Ancient glass] (has a section mentioning devitrification)]

Other uses

*When applied to whiteware ceramics, vitreous means the material has an extremely low permeability to liquids, often but not always water, when determined by a specified test regime. The microstructure of whiteware ceramics frequently contain both amorphous and crystalline phases.
*A vitreous luster in mineralogy refers to a glassy luster or sheen of a mineral surface. The minerals quartz and fluorite exhibit a vitreous luster.
*The vitreous humour (British spelling) or vitreous humor (U.S. spelling) is the clear gel that fills the space between the lens and the retina of the eyeball of humans and other vertebrates.

ee also

*Amorphous
*Glass
*Vitrification

References


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  • Vitreous — Vit re*ous, a. [L. vitreous, from vitrum glass; perhaps akin to videre to see (see {Vision}). Cf. {Varnish}.] 1. Consisting of, or resembling, glass; glassy; as, vitreous rocks. [1913 Webster] 2. Of or pertaining to glass; derived from glass; as …   The Collaborative International Dictionary of English

  • vitreous — (adj.) 1640s, from L. vitreus of glass, glassy, from vitreum glass, which perhaps was so called for its color (Cf. vitrium woad ). Vitreous humor attested from 1660s …   Etymology dictionary

  • vitreous — [vi′trē əs] adj. [L vitreus, glassy < vitrum, glass] 1. a) of, having the nature of, or like glass; glassy b) derived from or made of glass 2. of the vitreous humor vitreousness n …   English World dictionary

  • vitreous — ● vitreous nom masculin (mot américain) Nom générique de produits céramiques se situant entre les faïences fines feldspathiques et les grès fins blancs …   Encyclopédie Universelle

  • vitreous — ► ADJECTIVE 1) like glass in appearance or physical properties. 2) (of a substance) derived from or containing glass. ORIGIN Latin vitreus, from vitrum glass …   English terms dictionary

  • Vitreous — A clear, jelly like substance that fills the middle of the eye. Also called the vitreous humor, humor in medicine referring to a fluid (or semifluid) substance. * * * 1. Glassy; resembling glass. 2. SYN: v. body. [L. vitreus, glassy, fr. vitrum,… …   Medical dictionary

  • vitreous — I. adjective Etymology: Middle English, from Latin, from vitrum glass Date: 14th century 1. a. resembling glass (as in color, composition, brittleness, or luster) ; glassy < vitreous rocks > b. characterized by low porosity and usually… …   New Collegiate Dictionary

  • vitreous — 1. adjective a) Of, or resembling glass; glassy b) Of, or relating to the vitreous humor of the eye 2. noun The vitreous humor …   Wiktionary

  • vitreous —   a. pertaining to or like glass.    ♦ vitreal, a.    ♦ vitrescent, a. becoming vitreous; able to be made into glass.    ♦ vitrescible, a. vitrifiable.    ♦ vitric, a. glassy.    ♦ vitrics, n. study of glassware.    ♦ vitrifacture, n. making of… …   Dictionary of difficult words

  • vitreous — adj. 1 of, or of the nature of, glass. 2 like glass in hardness, brittleness, transparency, structure, etc. (vitreous enamel). Phrases and idioms: vitreous humour (or body) Anat. a transparent jelly like tissue filling the eyeball. Derivatives:… …   Useful english dictionary

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