354 Mallet — Stony Meteorite from Goon Butte, Arizona. 



I was interested in again finding in iron of meteoric origin 

 minute amounts of both copper and tin, having in former 

 years identified both these metals as constituents of the 

 Augusta Co., Va., and Wichita Co., Texas, meteoric irons. In 

 the case of the Coon Butte meteoric stone none of the granules of 

 nickel-iron exceeded - 5 or •6' 1,m in diameter. 



The feldspathic mineral supposed to be maskelynite was cal- 

 culated from the alumina found, assuming (on the basis of 

 Tschermak's analyses) that this forms 25 per cent of the min- 

 eral so named, assigning to this (on the same basis) silica in 

 the ratio A1 2 3 : Si0 2 = 25 : 55, and adding lime and the oxides 

 of the alkaline metals as actually found. Lithium was tested 

 for, but could not be detected. With these assumptions the 

 percentage composition of the mineral in question is 



SiO„ 55.00 I , 



A1.6, - 25-00 f aSSUmed 



CaO 14-17 



Na a O --- 5-93 



K„0 1'72 



101 82 



As most of these constituents were found partly in the por- 

 tion soluble and partly (to a larger extent) in that insoluble in 

 hydrochloric acid, it is probable that the feldspathic mineral is 

 attacked, though not readily, by that acid. But it is of course 

 quite possible that some of these constituents may belong to 

 the other silicates present. The supposition of Tschermak 

 that maskelynite is simply a feldspar that has cooled from fusion 

 in an amorphous state seems quite reasonable and likely. 



Olivine was calculated from the remaining constituents of 

 the portion left by the magnet and decomposed by hydro- 

 chloric acid, after deduction of the small quantities of iron, nickel 

 and other minor constituents already disposed of as above, and 

 also those of the maskelynite (?) to the extent indicated by the 

 alumina, etc., found in this portion decomposed by hydrochloric 

 acid. Thus calculated, the olivine gives the following per- 

 centage figures — 



Si0 2 42-29 



Ti0 2 -01* 



Ms;0 42-44 



FeO _.. 13-57 



98-31 

 * More exactly - 006. 



