872 REPORT OF NATIONAL MUSEUM, 1897. n 



l{ 

 buried in the earth, aud have been called by some persons, "cache 

 implements.'' M. de Mortillet names them generally Soliitreeii, after 

 Solutre, the representative station of his third epoch of the Paleolithic | 

 l)eriod, but specifically ho employs the name "feuille de laurier" (laurel 

 leaf). In the classification of arrowpoints and spearheads (see p. 890) 

 that form is assigned to ])ivision I, Class A. Caches, as will be seen by 

 the list (Appendix B, p. 970), are not exclusively of these implements; 

 therefore the term cache implements is not sufficiently definite and 

 should not be employed. Caches have been found of the large chipped ai 

 flints, "spades" or "agricultural implements,'' arrowi^oints and spear- 

 heads of different types, grooved axes, polished-stone hatchets, scrapers, 

 and other implements. 



Implements similar in material and identical in form with arrowpoints 

 and spearheads have been found throughout the western and south- 

 western United States, but which, from their large size, could hardly 

 have served for arrows or spears. An implement one to three inches 

 long M'e recognize as an arrowpoint, one four to six inches long as a 

 spearhead; but Mhat shall we say as to one a foot or fifteen inches 

 long? The U. S. National Museum possesses many of these specimens. 

 They can not be ignored, and so have been assembled and reported in 

 Appendix C (p. 982). 



V. MATERIAL OF ARROWPOINTS AND SPEARHEADS. 



Composition and structure — No jyractieal difference het ween the flint of 

 Europe and that of the United States — Microscopic examinations. 



It has been shown that flint was the favorite material in prehistoric 

 times for the manufacture of arrowpoints and spearheads and, indeed, 

 for all chippedstone implements, and was used by prehistoric man 

 wherever obtainable. Flint, as is well known, is a variety of quartz; 

 the principal difference so far as concerns the chemical constituents 

 arising from the impurities. Quartz, also much used in prehistoric 

 times in the manufacture of arrowpoints, is pure silica. It is 810^= 

 silicon 46.67, oxygen 53.33. Its hardness is 7 in the scale of 10, and 

 specific gravity 2.6 to 2.7. James D. Dana^ divides quartz into two 

 varieties, vitreous and cryptocrystalline. He divides the latter into 

 the chalcedonic and jaspery varieties. The vitreous is distinguished 

 by its glassy fracture, and the chalcedonic has a subvitreous or waxy 

 luster and is translucent. These owe their peculiarities either to crys- 

 tallization, mode of fabrication, or impurities. The commou impurities 

 of quartz, Dana says, are oxides of iron, clay, chlorite, or other miner- 

 als which produce opacity. 



Of the first variety, the rock crystal is the representative. It is pure 

 pellucid quartz. But such varieties as rose quartz, smoky quartz, 

 false topaz, and amethyst are produced in one or more of the ways 



' Manual of Geology, 1876, p. 52. Manual of Mineralogy and Lithology, 1886, p. 234. 



