Vermiculite


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Related to Vermiculite: Vermiculite Concrete

vermiculite

[vər′mik·yə‚līt]
(mineralogy)
(Mg,Fe,Al)3(Al,Si)4O10(OH)2·4H2O A clay mineral constituent similar to chlorite and montmorillonite, and consisting of trioctahedral mica sheets separated by double water layers; sometimes used as a textural material in painting, or as an aggregate in certain plaster formulations used in sculpture.

Vermiculite

A generic name for treated minerals which are used for insulation and fire protection, often as an aggregate in plaster or concrete.

Vermiculite

 

a mineral of the hydromica group with a schistous structure and additional interlaminate molecular water. Upon heating, small vermiform rods are formed from the layers of vermiculite. Chemical composition corresponds approximately to the formula Mgx(Mg, Fe)3 x[AlSi3 O10] · (OH)2 · 4H2O. It crystallizes in a monoclinic system and forms laminated aggregates or large laminated crystals of a golden yellow or brown color. Hardness on the mineralogical scale, 1-1.5; density, 2400-2700 kg/m3. It is not susceptible to pulverization and is similar to graphite in lubricating qualities.

When heated to a temperature of 900-1000° C, vermiculite swells (as a result of flaking of particles under the influence of evaporating interlaminate water), with an increase in volume of 15-20 times. Interlayers of air arising between the scaly layers of the mineral cause low density and high heat-and sound-insulating properties of exfoliated vermiculite. Vermiculite is a product of secondary change in dark micas (biotite and phlogopite). Commercial deposits of vermiculite in the USSR are known on the Kola Peninsula (Murmansk Oblast) and in the Urals (Cheliabinsk Oblast); and abroad, in the USA (Montana, Colorado, Wyoming, North Carolina, and Georgia) and in western Australia. Vermiculite is used in construction for the manufacture of heat-insulating products, sound-absorbing materials, lightweight concrete, and plastering solutions; as a filler in rubber, plastic, paints, chemical pesticides; in the manufacture of antifriction materials; and in agriculture, to improve soil structure.

vermiculite

A natural mica expanded by heat(i.e., exfoliated) to form lightweight thermal insulating
References in periodicals archive ?
These changes are the result of the close collaboration of government officials, the world's most respected scientists in the area of vermiculite and members of our industry.
We're wondering if the inspector didn't want to go into the attic due to the vermiculite.
Hydroxy-interlayered vermiculite has been commonly identified in soils (Toksoy-Koksal et al.
For potting the herbs a good potting soil is fine or you can mix the soil with compost, perlite, or vermiculite.
In addition to vermiculite insulation, many older homes contain serpentine asbestos in commercial products such as thermal insulation, floor tiles, roofing tiles or shingles, gaskets, ceiling texture materials, and siding (Dodson & Hammar, 2006).
ashei and vermiculite litter) in the present study may have been caused by soil aeration.
Vermiculite is a scarce mineral that has been mined domestically only in Virginia, South Carolina, and Montana.
Your installation spill response team should neutralize any puddles of DS2 with sodium bisulfate, NSN 6810-00-270-9984, and soak it up with vermiculite insulation.
5 million to reimburse the federal government for the cost of investigating and cleanup at a former vermiculite mine in Libby, MT, that turned out to be contaminated with asbestos.
Vermiculite ore--containing high concentrations of asbestos--was mined at Libby between 1923 and 1990, and accounted for most of the world's vermiculite.
Grace operated a vermiculite mine and mill it purchased from the small Zonolite Company in 1963.