Document QgkOk5n9wZnjDB1QDNDyBkRD5

treble 3-1: Varieties t>f_ j> sbe stos Chrysotilc White Asbestos Mo 3 (Si^05) (0H)4 Asbestos Arophiboles Actinolite (Si8o2?) (om? Aroosite (Fe,K.g)? <oh)2 Asbestos has been know.*?) to n.ankino for a lono ;*riod of time,early evidence of its use going hack to the stcnc-ngo. As a r.aterial of ccwfucrcial importance, asbestos commenced its role in itchnolooy around I860 when largcscalc ndnin^^operation^ of chrysotilc started in Canada and Russia. The mining of crocidolite and emosite on anything like a cor^nercial scale began somewhat later, around 1900. While chrysotilc occurs abundantly in several deposits throughout the world, this is not true of the arcphibole fibres which can only be found in a few specific regions, which are commer cially important. They are more widely distribvited in smaller quantities. Of those omphibole fibres cnly crocidolite *nd *r;:Ocite are at present pro* duced on a commercial scale, ribrous trerclitc is C:\Jittle economic Arcportancc. ribrous antbophyl 1 itc was mined in Piiiis./* but c*J.<s was disconti nued during 1975. fibrous actinolite is no ;..ore than * curiosity. Approxi mately 9f\ of all asbestos produced is chrysotile v.*hilst the remainder consists r.sainly of emosite and crocidolite. An r.bC country in which I chrys of th which of nc Icvei the } end f the re 8Ri has t iicr c ting as i man a six i?.ay Pli' fill con t vr v. i t t V,. 1 Bt>01 >711 PRODUCED BY FORD