HARRISON COUNTY. 149 



The following is an analysis of this clay dried at a temperature of 115° C: 



Silica 73.11 



Alumina 17.77 



Iron 2.83 



Lime 0.40 



Soda 3.02 



Potash 2.76 



Magnesia 0.28 



100.17 

 3. POTTERY CLAYS. 



As compared with fire clays pottery clays are more plastic and adhesive on 

 account of the greater proportion of contained alumina. Pottery clays have 

 also a wider range in the proportions of their constituents, and generally con- 

 tain more impurities, besides it is not necessary that these clays should con- 

 tain such refractory properties as fire clays. Any plastic clay capable of 

 withstanding a heat high enough to enable it to "frit" without actual fusion 

 is suitable for pottery use, provided it does not contain too large a proportion 

 of impurities. 



Clays suitable for the manufacture of the ordinary grades of earthenware 

 occur in great quantities in Harrison County. Some of these clays are highly 

 aluminous, but the greater proportion of them contain considerable quantities 

 of sand, either mixed throughout the body of the mass of clay or in thin 

 strata or layers interlaminated with the clay beds. 



The gray clays of the region north of the Little Cypress and the alumi- 

 nous clays found on the Lewis Watkins headright may be utilized for the 

 manufacture of a good grade of earthenware. The clays found in the Huff- 

 man section, especially Nos. 5 and 7, belong to the list of plastic clays and 

 may be used for the manufacture of such articles as jugs, jars, churns, fruit 

 jars, etc. 



The clay found on the south side of the Peter Whetstone headright, and 

 already described among the fire clays, may be utilized as a pottery clay if 

 used in combination with some other more aluminous clay. This clay was 

 used for the manufacture of earthenware some twenty-five years ago. The 

 work was carried on for a year or two, and then abandoned on account of 

 some difficulties connected with the firing or burning of fhe ware. The loss 

 from this source was about twenty-five or thirty per cent. Judging from the 

 numerous fragments still lying around the site of the kiln, the ware made 

 was rather open in texture. This clay admitted of both a " salt " glaze and a 

 glaze made from ashes. It will also admit of a black or "Albany slip" glaze. 

 When salt glazed, the ware is a creamy white with a faint tinge of brown 

 through it. Ash glaze gave the ware a greenish black hue. 



This clay can be materially improved by the addition of a more aluminous 



