Keyes — Meteorites on the Painted Desert. 149 



igneous masses appear to be in need of careful revision. 

 The meteoritic phase has received as yet insufficient ap- 

 plication. That it is far more important than has been 

 suspected is clearly shown by recent observations on 

 desert ores. That this is the main source of vadose ore 

 materials now seems not unlikely. It is probable that 

 much of the so-called general metallic content of the sedi- 

 mentary rocks is in reality derived immediately from 

 meteoritic sources, for its derivation entirely from the 

 country-rock of mining districts especially those far re- 

 moved from volcanic activity, has never been a very sat- 

 isfactory explanation. 



The supplies of metaliferous materials derived from 

 meteoritic sources, inferentially at least, equal if not 

 actually greatly exceed in amount those derived from the 

 secular decay of rock-masses. It is also a question 

 whether of the worked ore-bodies of the world the ma- 

 jority of mines are not really operated in the so-called 

 vadose ores. Casual perusal of the vast descriptive lit- 

 erature on the mines of the world appears to give ample 

 support to this statement. 



Resume. 

 From the foregoing notes it may be inferred: 



(1) That Coon Butte is most probably of volcanic ori- 

 gin ; the direct evidences being the numerous similar phe- 

 nomena in the vicinity showing undoubted connection 

 with the explosive type of vulcanism. 



(2) That the great abundance of meteoritic materials 

 in the neighborhood of Coon Butte is due to favorable 

 climatic conditions coupled with marked deflative activity 

 on a hard rock stratum rather than to extensive comminu- 

 tion of a huge meteorite falling at this point. 



(3) That as compared with the conditions afforded 

 by moist lands desert regions generally are exceptionally 

 favorable for the disclosure of abundant meteoritic ma- 

 terial. 



