496 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1935 



Each case of patination, therefore, has to be treated independently, 

 and whatever comparisons are instituted the resulting conclusions 

 can have only the merest general significance. 



With these precautions in mind, it is legitimate to cite sporadic 

 instances of American patination. To begin with, our petroglyphs, 

 or abraded rock-pictures, of the Southwest and elsewhere, admirably 

 illustrate the j)henomenon in all its stages, from fresh-looking artifi- 

 cial surfaces to such as have weathered into an exact resemblance of 

 the adjacent natural crust. In our collections from Texas and other 

 parts of the country, and even in the literature, occasional stone im- 

 plements appear which exhibit a worn, shiny, polished surface, much 

 like that produced on natural pebbles by the action of blown desert 

 sands.** As examples of chemical action may be mentioned the 

 chipped argellite implements from the yellow soil at Trenton, which 

 exhibit a graduated alteration in the rock substance from the surface 

 inward, reaching depths measuring appreciable fractions of an inch. 

 Lastly, it is necessary to mention the claims made by the late Prof. 

 N. H. Winchell concerning the degrees of patination exhibited by a 

 large collection of flaked chert material gathered for him by J. V. 

 Brower in northeastern Kansas, Winchell, after much study of his 

 material, distinguished no less than six stages of patination, or, 

 better expressed, six successive attempts at flaking the specimen into 

 shape. Four of these stages he regarded as of Neolithic date and 

 workmanship, while the other two were declared to be Paleolithic.*^ 



Critical comment on both the facts and their interpretations, as 

 outlined, is obviously premature, although called for in some form. 

 Winchell's bold effort to prove the antiquity of man in America 

 reminds one strongly of the earlier attempts by Thomas Wilson; 

 yet, although Winchell's method was essentially sound, his conclu- 

 sions are scarcely more acceptable until his material has been checked 

 over by someone thoroughly familiar with artificially worked rock 

 surfaces. From what little I have personally been able to see of the 

 Kansas collection stored at the Minnesota Historical Society Mu- 

 seum in St. Paul, I am far from convinced of anything like six 

 discernible artificial surface conditions; but even if they exist, it 

 does not follow that any of them are necessarily of Pleistocene date. 

 We need here, as in the Trenton case, to have the opinion of both 

 the mineralogist and the chemist as to what has really happened, and 

 whether or not time is a uniformly important factor in the process. 

 Furthermore, cur most patinated artifacts are not of true flint like 

 those of Europe, so that comparison is out of the question. When 



"Moorhead, W. K., The Stone Age in North America, vol. 2, pp. 352-3, 1910; Winchell, 

 N. n., The weathering of aboriginal stone artifacts. Coll. Minnesota Hist. Soc, vol. 24. 

 pt. 1, pp. 151-168, pi. 15, 1916. 



15 Winchell, N. H., op. cit., pp. 37, 170. 



