248 



AKNTJAL REPORT SMITHSONIAN ESTSTITUTIOOSr, 1942 



out from the ground mass surrounding the area, leaving the taenite 

 segregated ; hence, localized areas of kamacite and taenite occur. 



STONY METEORITES 



The metallic inclusions in stony meteorites will be only briefly dis- 

 cussed. The principal point to be brought out is the similarity in 

 range of chemical composition of the iron in stony meteorites and in 

 iron meteorites. The composition of the metal in stony meteorites of 

 the chondritic group seems to change as the proportion of the metal 

 to the silicates varies. When there is an abundance of metal, its 

 cobalt-nickel content is usually relatively small ; likewise when only a 

 few metallic inclusions occur they are usually very rich in cobalt and 

 nickel. 



Table 4.- 



Fe 



-Comparison of the molecular ratio index „ , of iron in meteorites 



" The analyst failed to determine the percentage of Co. 



Several authors have called attention to this fact and other tables 

 have been published.^ An independent check was made of this point 

 by selecting at random a limited number of well-studied chondritic 

 meteorites and arranging them in a series starting with the specimen 

 having the highest index ratio to determine whether some correlation 



' Prior, G. T., Min. Mag., vol. 18, p. 26, 191C. 



