ALABAMA MICA DEPOSITS 31 



Decoration: Sheets of mica form the material on 

 which pictures and portraits are painted and for inlay 

 work. Ground mica is used extensively for decoration in 

 wall paper, processional ornaments, fancy paints, orna- 

 mental tiles, and concrete. 



Lubrication: For wooden and metal bearings and 

 for tire powder. 



Filler: Patent roofing material, rubber goods, but- 

 tons, absorbent for nitro-glycerine, and various other 

 products. 



Miscellaneous: Calico printing, to prevent sticking of 

 tar papers, medicinal uses (India only) etc. 



*A recent classification of these uses of mica, based on 

 their relative importance, is as follows : 



Essential uses: Electrical insulation films, sheets, 

 washers, splittings, and built-up mica board. 



Less essential uses : Stove front, lamp chimney and 

 shades, electric heating devices, pipe and boiler cover- 

 ings, roofing material, annealing steel, lubricant for 

 wooden bearings. 



Non-essential uses : Phonograph diaphragms, decora- 

 tion, lubricant for metal bearings, filler for rubber and 

 various materials. 



Consumption of mica by the industries would largely 

 base as to relative amounts, although not necessarily in 

 respect to prices paid, on the above classification of uses. 



Commercially speaking, splittings refer to sheets ap- 

 proximately about one thousandth of an inch in thick- 

 ness, which thin sheets are manufactured by special pro- 

 cesses into molded and built up forms variously known 

 to the trade as micanite, micabeston, micabond, micadem- 

 ite and others, used extensively for electrical insulation. 



Sheet mica finds its uses as above indicated in all 

 three of the classes of essential, less essential and non- 

 essential uses, and constitutes the most important and 

 largest part of the mica industry. As commercially pre- 

 pared, it ranges in sizes from what is known as punch 

 mica, for the manufacture of disks and washers of at 

 least l l! 2 inches in diameter, on up to the largest sheet 



*U. S. Bureau of Mines Mica in 1918. 



