ie: FrkLp CoLUMBIAN MusEuM—GEOLOGY, VOL. III. 
I]. OCTAHEDRITES. 
The meteorites of this class are the most abundant among iron 
meteorites. According to the width of the lamelle as seen in etched 
sections, they are divided as follows: Coarsest octahedrites, lamelle, 
many mm. to 2.5 mm. in width; coarse octahedrites, lamelle 2—-1.5 
mm. in width; medium octahedrites, lamellze 1.0-0.5 mm. in width; 
fine octahedrites, lamellz o.4-0.2 mm. in width; finest octahedrites, 
lamelle from o.2 mm. down. While no sharp line of separation can 
be drawn between these groups, the members of each group present as 
a rule characters more or less peculiar to themselves. As compared 
with the hexahedrites, the octahedrites differ in structure in being 
made up of lamelle arranged in accordance with the planes of the 
octahedron. These lamelle in turn are composed of two or more 
alloys of nickel-iron. In composition a higher percentage of nickel- 
cobalt may be noted among the octahedrites, as compared with the 
hexahedrites, and schreibersite and troilite are far more abundant 
than in the hexahedrites. Cohenite, which is not known to occur in 
the hexahedrites, is characteristic of certain groups of the octahe- 




COAR 
Name. | Fe. | Ni. | Goo }-Cuy | Cretaares S, | Ci eee | ci. | I | Miscellane 
ATS DGice ss aa et pcs 92.27 ig lola hon we ee ee 
Canyon Diahlo::.:.195°370/3.045|-= 24 (4-a5leo =e ST AA] tries] See tra ees R2OTR LG << ane 
és we ee O12 3001704) one Dele ee .179 004 417) ..O47| 2, VGei Glee ee aa 
CANTO sae k ate cte wets 91.96 ee SOuOscee edad .O1). pene tf. 1 a ee ee 
Central Missour. 32 94.73, |4-025|a2TOtlssealene 44 .O2 ,O1' | 5... 2, Dedee ete eee 
Nelson County....'93.10 [6.11 | .41 | tr. ]....] .05 | 
Pitteburcar oe eaves ee 4:66 | 39 |-63-|-..-1 225 |) vo4 |-4. 2.) eee ae en 
PO ee Po an} 93-38: |5-09%|12242|.05 1.02 P15 07 .... Chromite 
Ponca, CTeEek Wes. GT. 74.10.534[> ob daeealcacep sOL 0 |stac.e| at see) eee Si 2a 
: Pe Ee renee Ole 74" 17 208: Le tea eee ee Me) Meee PSP eR I 
Sao juliagtye 2.22; 89.39 Ges tr. 26 
er 
seelasrenck.. ta Q0 40015 <3 AS one Tb. eee Peers tence oe hae eS 83|M: 
ad A eae 6253316422") 20670 he eee hens fees 52.4 :O2 "take om 18|Cu, 4-50 
