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Oldenburg, Germany, one of the principal manufacturing cities of this material, is about twenty-five cents per pound, and the beauty of the varieties occurring in Texas would add materially to that price.

PUDDING STONE.—Of equal beauty with the agates are some varieties of metamorphosed pudding stones brought from the lower mountains by Prof. Streeruwitz. They take fully as fine a polish, and the variety of color and shape of the inclusions are very pleasing.

SERPENTINE.—Some of the serpentines of West Texas will be valuable as ornamental stones. So far no "precious serpentine" has been found, but some of the red and green varieties will come into use as the region is developed. Central Texas also affords varieties which may be utilized.

SILICIFIED WOOD.—While the greater part of the silicified wood of the State is not of much value as an ornamental stone, there are certain horizons in the Fayette Beds in which the wood has been opalized and presents a pleasant variety of color and banding. These will probably be used quite largely for various purposes in ornamental work so soon as their beauty is properly shown.

PEARLS.—Texas is one of the principal pearl producing States of the United States. Mr. Kunz,-in "Gems and Precious Stones," mentions one from Llano valued at ninety-five dollars, which was sold in New York. The pearls are found in the Unios, or fresh water mussels, which abound in the Colorado, Llano, and Concho rivers, and many other streams in Texas. They have been collected in large numbers, and in collecting them great numbers of the shell fish have been destroyed. In order to avoid this wholesale destruction, and leave the animal to propagate more valuable progeny, Mr. Kunz recommends that instruments similar to those used in Saxony and Bavaria be introduced here. One of these is a flat iron tool, the other a pair of sharp pointed pliers, both fashioned for the purpose of opening the shells for examination without injury to the animal, which, if no pearl is found, is replaced in the shoal.

ALABASTER.—Alabaster of fine grain and translucency occurs both among the rocks of the Cretaceous formation and in the gypsum region of the Permian. Its uses in vases and statuary are well known, and material suitable for any of these purposes can be secured in any desired quantity.

REFRACTORY MATERIALS.

Refractory materials, or those which will stand very high degrees of heat without injury, are of the highest importance in manufacturing.