Chrysotile asbestos

Chrysotile is an asbestiform sub-group within the serpentine group of minerals. There are three known species of chrysotile: clinochrysotile (which is monoclinic), orthochrysotile (which is orthorhombic) and parachrysotile (which is also an orthorhombic polymorph). These varieties are all phyllosilicates. The chemical formulae for the three are the same: Mg₃(Si₂O₅)(OH)₄ with variable iron as Fe²⁺ substituting for magnesium. Chrysotile varies in color from gray-white to golden yellow to green. It has a hardness of 2.5 - 3. The three varieties form the fibrous members of the serpentine group and have been extensively mined as asbestos. Asbestos (chrysotile). ... Asbestos (chrysotile). ... Look up asbestiform in Wiktionary, the free dictionary. ... For other uses, see Mineral (disambiguation). ... In crystallography, the monoclinic crystal system is one of the 7 lattice point groups. ... In crystallography, the orthorhombic crystal system is one of the 7 lattice point groups. ... The silicate minerals make up the largest and most important class of rock-forming minerals. ... General Name, symbol, number magnesium, Mg, 12 Chemical series alkaline earth metals Group, period, block 2, 3, s Appearance silvery white solid at room temp Standard atomic weight 24. ... Not to be confused with Silicone. ... This article is about the chemical element and its most stable form, or dioxygen. ... This article is about the chemical element and its most stable form, or dioxygen. ... This article is about the chemistry of hydrogen. ... General Name, symbol, number iron, Fe, 26 Chemical series transition metals Group, period, block 8, 4, d Appearance lustrous metallic with a grayish tinge Standard atomic weight 55. ... General Name, symbol, number iron, Fe, 26 Chemical series transition metals Group, period, block 8, 4, d Appearance lustrous metallic with a grayish tinge Standard atomic weight 55. ... General Name, symbol, number magnesium, Mg, 12 Chemical series alkaline earth metals Group, period, block 2, 3, s Appearance silvery white solid at room temp Standard atomic weight 24. ... For other uses, see Asbestos (disambiguation). ...

Chrysotile serpentine from the Salt River area Arizona

Clinochrysotile is the monoclinic form of chrysotile and likely the most common variety. Like the other two species of chrysotile (orthochrysotile and parachrysotile) it is very difficult to distinguish from the other species in hand specimens. When the fibers are examined using polarized light microscopy the high refractive index is oriented parallel to the long axis of the fiber. Its two measurable refractive indices tend to be lower than those for Orthochrysotile. Its type location is unknown although the chrysotile from Asbestos, Quebec, Canada is largely clinochrysotile. Image File history File links Chrysotile serpentine, Salt River, Arizona. ... Image File history File links Chrysotile serpentine, Salt River, Arizona. ... Asbestos is a town in southeastern Quebec, Canada on the Nicolet River and is the seat of the MRC dAsbestos. ...

Orthochrysotile is the orthorhombic form of chrysotile and is more common than the other orthorhombic form parachrysotile. Like the other two species of chrysotile (clinochrysotile and parachrysotile) it is very difficult to distinguish from the other species in hand specimens. When the fibers are examined using polarized light microscopy the high refractive index is oriented parallel to the long axis of the fiber. Its two measurable refractive indices tend to be higher than those for Clinochrysotile. Its type location is found in Silesia. In crystallography, the orthorhombic crystal system is one of the 7 lattice point groups. ... Silesia (English pronunciation [], Czech: ; German: ; Latin: ; Polish: ; Silesian: Ślůnsk) is a historical region in central Europe, located along the upper and middle Oder River, upper Vistula River, and along the Sudetes, Carpathian (Silesian Beskids) mountain range. ...

Parachrysotile is a second orthorhombic form of chrysotile. It is also refered to as alpha-Chrysotile in some references. Like the other two species of chrysotile (orthochrysotile and clinochrysotile) it is very difficult to distinguish from the other species in hand specimens. When the fibers are examined using polarized light microscopy the high refractive index is oriented perpendicular to the long axis of the fiber. Photomicrographs of parachrysotile with clinochrysotile are available on the microlabgallery.com site. Its two measurable refractive indices tend to be higher than those for Clinochrysotile. Its type location is Québec, Canada.

Carcinogenity

Chrysotile, a mineral used for asbestos, is a human carcinogen, though there has been considerable debate by the companies who use it over whether its potency approaches that of amphibole forms of asbestos. The question of whether "pure" chrysotile carries as great a risk as amphibole fibers is in any case largely academic, in that many chrysotile ore deposits do contain amphibole fiber asbestos such as tremolite, crocidolite and actinolite. Most commercial chrysotile in the US, for example, is contaminated with tremolite.^{[citation needed]} Image File history File links Emblem-important. ... For the logical fallacy, see Amphibology. ... A sample of tremolite Tremolite is a member of the amphibole group of silicate minerals with composition: Ca2Mg5Si8O22(OH)2. ... Amphibole (Hornblende) Amphibole defines an important group of dark-colored rock-forming inosilicate minerals composed of double chain SiO4 tetrahedra linked at the vertices and generally containing ions of iron and/ or magnesium in their structures. ... Well-cleaved, dark, fine-grained chlorite-actinolite metadiabase intrudes light granitic gneiss Actinolite is an inosilicate mineral with the chemical formula Ca2(MgFe)5Si8O22(OH)2 // Mineralogy Actinolite is an intermediate member in a series between tremolite (Mg-rich) and ferro-actinolite (Fe-rich). ...

A good reference for the health effects of exposure to Chrysotile asbestos is the book by Nolan et al.

References

• Webmineral
• Mindat clinochrysotile
• Mindat orthochrysotile
• Mindat parachrysotile
• Asbestos-containing Floor Tile and Mastic Abatement: Is there Enough Exposure to Cause Asbestos-related Disease?
• Deer, W. A., R. A. Howie, and J. Zussman, AN INTRODCUTION TO THE ROCK-FORMING MINERALS, ISBN 0-582-30094-0, pp. 344-352, 1992
• Ledoux, R. L. (ed), SHORT COURSE IN MINERALOGICAL TECHNIQUES OF ASBESTOS DETERMINATION, Mineralogical Association of Canada, pp. 35-73, 185, 1979.
• http://www.microlabgallery.com/ChrysotileFile.aspx
• Nolan, R. P., A. M. Langer, M Ross, F.J. Wicks, and R.F. Martin (eds), THE HEALTH EFFECTS OF CHRYSOTILE ASBESTOS, The Canadian Mineralogist, Special Publication 5, 2001.