Phillips — Vanadium in Sedimentary Rocks. 173 



Art. XVI. — A Possible Source of Vanadium in Sedimen- 

 tary Rocks; by Alexander H. Phillips. 



Included in the materials collected at the Tortugas and 

 analyzed for metals (some of the results of which were 

 reported and published in the annual report of the Car- 

 negie Institute for 1917) , was a brown spotted holothurian, 

 Sticopus mobii, which was analyzed by the methods there 

 indicated. When the ash from this material was dis- 

 solved in hydrochloric acid, a deep blue solution was 

 obtained, resembling in depth of color that of a saturated 

 solution of copper sulphate, but to my great surprise this 

 color was not due to copper but to vanadium. The 

 material when collected was cleaned of all sand externally 

 and the sand content of the intestines was also removed. 

 It was then dried at 110° C. 



The amount of each constituent determined in a 

 20 gram sample of this dried material is here expressed 



grams. 









Copper 



Iron 



MnO 



Vanadium 



•0009 



•0178 



•00022 



•0247 



The amount of the element vanadium in this material 

 is 0-123 per cent of the weight of the entire animal dried 

 at 110 C C. 



Vanadium, I believe, has never been reported from sea- 

 water ; however, this holothurian must have collected its 

 vanadium either directly from the seawater or from its 

 food which in turn must have concentrated it from the 

 seawater. 



The Tortugas are far enough removed from the con- 

 tinental shore or the mouth of any river, not to be 

 influenced by the sediments carried into the gulf. Their 

 formation is practically entirely that of carbonates of 

 calcium and magnesium, both of which are either of 

 organic or precipitated origin. 



Occurrence of Vanadium. — Vanadium occurs dis- 

 seminated in small quantities in almost all igneous rocks. 

 There^are, however, few localities in igneous rocks where 

 it has been concentrated in sufficient quantities to pay 

 commercially for the labor of mining. The source of 

 commercial vanadium is practically that of the sedimen- 

 tary rocks or coals. 



Vanadium has been reported in a fresh water from 

 Brookline by A. A. Hays, and in the blood of an acidian 



