| Abstract |
One hundred talc samples have been analyzed by polarized light microscopy, dispersion staining, x-ray diffraction and, when necessary, by transmission electron microscopy and electron microprobe. The analytical methods were refined in scope, sensitivity and accuracy as a part of the project. The samples ranged from 1 to 99% talc with an average of 63%. Twenty-three other minerals were identified including the serpentines: antigorite, lizardite and chrysotile; the amphiboles: anthophyllite, tremolite and actinolite; the carbonates: calcite, dolomite, ankerite and magnesite; the talc-like mineral chlorite as well as quartz, mica, feldspars, magnetite, coal, graphite, hydroxygaptite, clays, hydrous iron oxides and rutile. Chrysotile was found in only one sample which, however, contained only 1-2% talc. More than one-third of the samples contained tremolite or actinolite often in major amounts and usually partly fibrous. This report was submitted under the sponsorship of the National Institute for Occupational Safety and Health. |
