itting, pounding, perforating, and scraping implements are generally derived from schists, basaltic, trachytic, and porphyritic rocks, and those for grinding and crushing foods are more or less composed of coarse lava and compact sandstones. Quite a number of the metate rubbing stones and a large number of the axes are composed of a very hard, heavy, and curiously mottled rock, a specimen of which was submitted to Dr. George W. Hawes, Curator of Mineralogy to the National Museum, for examination, and of which he says:
"This rock, which was so extensively employed by the Pueblo Indians for the manufacture of various utensils, has proved to be composed largely of quartz, intermingled with which is a fine, fibrous, radiated substance, the optical properties of which demonstrate it to be fibrolite. In addition, the rock is filled with minute crystals of octahedral form which are composed of magnetite, and scattered through the rock are minute yellow crystals of rutile. The red coloration which these specim
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