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KAOLIN.

In addition to the kaolin already mentioned in Robertson County, kaolins of excellent quality are found in Edwards and Uvalde counties. These are pure white in color, somewhat greasy to the touch, and are infusible in the hottest blow pipe flame. Being practically free from iron, they are adapted to the making of the best grades of china. They are free from grit and every other objectionable impurity. A comparison of the analyses of these kaolins with those of established reputation will more fully show their value. The analyses of the Texas specimens are by Dr. Everhart, of the State University:

Of the other materials needed in the manufacture of pottery we have deposits of feldspar well suited for glazing; gypsum for the manufacture of plaster of paris for moulds; clays suitable for the saggers, and cheap fuel in abundance.

BUILDING MATERIALS.

BUILDING STONE.

The variety and widespread occurrence of the rocks of Texas suitable for construction is so great that it will be impracticable to allude to them in any other than general terms. They will therefore be grouped under general headings.

GRANITES.

Granites occur in widely separated portions of the State. The first locality is what has been termed in our reports the Central Mineral Region, the second is in the extreme west, or Trans-Pecos Texas. The granites of the first or Central region are of different colors. The best known is the red granite, such as was used in the construction of the Capitol building. The color is red to dark reddish-gray, varying from fine to rather coarse grain in structure, and susceptible of high polish.