ALABAMA MICA DEPOSITS 37 



The feldspar group occurring with the mica deposits, 

 mainly potash spars, with resultant kaolins are taken 

 out to greater or less extent in all mica recoveries, but 

 have received as yet in Alabama only limited tests and 

 no appreciable commercial use. From 20 to 40 per cent. 

 of ground feldspar enters into the composition of most 

 china and porcelain, as a bonding and dissolving medium 

 of the kaolin, ball clay, and ground flint. It has also a 

 wide range of minor uses. As a source of potassium 

 compounds, the potash spars received exhaustive testing 

 during the war, the results of which tests have not yet 

 6een fully made known. It has been stated however tha f 

 under present known methods a minimum of 12 per cent. 

 of potash is requisite for any profitable process for its 

 extraction from spar. 



Such high grade feldspar is hardly likely to be obtain- 

 able in this State in any large centralized amounts. Anal- 

 yses made of best native spars have averaged approxi- 

 mately 10 per cent, potash, although the samples tested 

 would otherwise class as No. 1 by reason of freedom 

 from iron bearing minerals, and as containing but lit- 

 tle muscovite and quartz, an allowable 25 per cent, of 

 quartz being permissible in No. 2 spar grade. 



The most important and valuable use of this mineral 

 would be its possible local value as ground feldspar for 

 a commercial fertilizer. The availability of potash in 

 finely ground feldspar has long been the subject of ex- 

 haustive practical tests, the results of which tests have 

 been conflicting under varying soil conditions. Tests 

 however under special conditions, made by the U. S. Bu- 

 reau of Plant Industry, representing the wide variance of 

 soils presented by Connecticut and Florida, have demon- 

 strated that plants. were able to obtain potash from very 

 finely ground feldspar. If such availability becomes 

 fairly assured through continued and systematic experi- 

 mentation Alabama spars may become of very positive 

 value. 



Crystalline quartz, of certain specified grades, has vari- 

 ous commercial uses. For acid towers, the sizes speci- 

 fied are termed "fist" to "head." 



