HARRISON COUNTY. 



151 



an oxide or sulphide in the shape of pyrites, mica, sand, alkalies, and lignite. 

 The most of these can be removed or overcome by judicious working or by 

 washing and grinding. Where pyrites occur in large pieces they ought to 

 be removed by cutting out of the clay before grinding. In many of the blue 

 clays iron pyrites occur disseminated through the clay ki small seams or iu 

 balls, and frequently in such small particles as to render the cutting impracti- 

 cable. Except for articles requiring a low temperature, or for the manu- 

 facture of alum, these clays are of no practical use. By the proper grinding 

 and working of clay, lignite can be rendered serviceable in the production of 

 heat while the ware is in the kiln. Its presence will render the bricks or 

 other ware more porous than necessary, but in most cases this will not mate- 

 rially affect the brick. Mica must be got rid of by washing. As a source 

 of potash this mineral is not desirable in clays of any description, especially 

 those intended for pottery or refractory purposes. 



TABLE SHOWING ANALYSES OF CLAYS COLLECTED IN HARRISON COUNTY. 



No. 



03 



< 



o 



I 

 3 



a 



OS 



e3 



O 



W 



1 

 o 





3 



© 



*812 x 



73.11 

 74.15 

 68.35 



17.77 

 14.11 

 16.22 



2.83 

 4.09 



4.08 



0.40 

 (t) 



0.28 



ft) 



1.08 



3 02 



2 7fi 





100 17 



+814 



•j-716 



J813 







2.20 

 2 90 3.20 



8.00 



99.93 



+815 







20.78 

 2.20 

 3.77 



1.56 

 1.57 

 2.53 



Trace. 

 0.60 



1.16 











♦817 1 



+818 2 



71.00 

 65.90 



82.10 

 68.90 

 75.30 



20.20 

 18.43 



14.24 



21.83 

 13.87 



Trace. 

 0.30 



6.16 

 4 08 



1.24 

 0.95 



6.36 



100.80 

 100 39 









+622 



821 3 



1.00 Chi. 

 4 00 Dhl. 





6.60 

 





929 



1.90 



1.23 



2.65 



2.62 



100.10 



1 Dried at 115° C. 2 Fuses at white heat. 3 Silica in the form ol sand, 25.23 per cent. 

 {Not determined. 

 Analyses made in the Laboratory of the Geological Survey of Texas by *J. H. Herndon, fL. E. Magnenat. 



Localities. 



No. 812. A. Dean headright. 



No. 814. J. Sanchez headright. 



No. 716. F. Wilson headright. 



No. 813. D. McG-ray headright. 



No. 815. W. B. Burres headright. 



No. 817. P. Whetstone headright. 



No. 818. D. McGray headright. 



No. 622. F. Wilson headright. 



No. 821. Lewis Walkins headright. 



No. 929. M. L. Eager headright. 



BUILDING STONE. 

 With the exception of the ferruginous sandstones there are no good build- 

 ing stones within the limits of Harrison County. Many of the indurated 



