104 E. T. Allen — Native Iron in Missouri. 



After solution in aqua regia a considerable residue of silica, 

 which was partly gelatinous, and some carbonaceous matter 

 remained. 

 Silica — 

 2*9929 gr. iron taken. Silica = -0495 gr. = 1*65 per cent. 



Iron — 

 The filtrate from silica was diluted to 500 cc and aliquot parts 

 were titrated with permanganate solution. 



a. 25 cc sol. required 23'08 cc KMn0 4 . 



b. 20 " " 18-47 

 l cc KMnO=: -006292 gr. Fe. 

 Iron = (a) 97*09 (b) 97-10 



The specimen analyzed was not examined until several 

 months after it was taken from the ground and, although all 

 the outer portions were carefully filed away before the analysis, 

 it was probable that the rust had penetrated deeply and that 

 small portions were unremoved. The original percentage of 

 metal was probably higher. 

 Phosphorus — 

 -105 cc of the nitrate mentioned above was examined for phos- 

 phorus. 



Mg 2 P 2 7 obtained = '0155 gr. P ±= -176 per cent. 

 Analysis. 



Iron _.. 97-10 



Silica 1*65 



Phosphorus ._ -176 



Carbon _ undetermined. 



Conclusion. — All the specimens here described were found 

 at such a depth from the surface and under such conditions 

 that there can be no doubt of their terrestrial origin. That 

 they were portions of the drill, is of course untenable, not only 

 because the drills remained intact but because of the remark- 

 able softness of the specimens, their peculiar structure (in the 

 case of the Cameron specimens) and the remarkable resistance 

 which two of them offered to the drill. The close connection 

 of two of them with coal and the location of the third in the 

 same geological formation (the Coal Measures) and in the com- 

 paratively near vicinity of coal, is significant of their origin, 

 though the minute quantity of carbon in the metal is notable. 

 Whatever the process of reduction, the location of the irons in 

 all three cases was very favorable to preservation. 



As regards composition, not only is the purity of these 

 specimens remarkable, but it is interesting to note the absence 

 of nickel, an element always found in meteoric irons, but 

 rarely in those of terrestrial origin. 

 School of Mines of the University of Missouri, 

 Rolla, Missouri. 



