Plate 41 



1. Cleveland, Tennessee; medium octahedrlte; Ni-Co 9-10 percent. Part of a large 

 field of very uniform lamellar plessite. Picral 50 seconds; X 45. 



2. Smith's Mountain, North Carolina; fine octahedrite; Ni-Co 8.52 percent. An area 

 of coarse granulated plessite. The kamacite granules show the same transformation struc- 

 ture as the adjacent kamacite band. Taenite bodies are more or less gray by reason of 

 supersaturation. In the larger taenite areas transformation is incomplete, leaving cores 

 of a dense unresolved gamma-alpha mi.xture. Picral 45 seconds; X 150. U. S. National 

 Museum. 



3. Pine River, W isconsin. An iron to be described by E. P. Henderson and the author, 

 which may be provisionally classified as an atypical coarsest octahedrite with accessory 

 silicates. A plessite field with a narrow taenite border. Upper right, a large irregular 

 inclusion of schreibersite. Light picral; X 60. 



4. Pine River. The same area as figure 3 with additional etching 5 minutes with neutral 

 sodium picrate. The shaded core is unaflFected, indicating that it does not contain phosphide, 

 but is a gamma-alpha aggregate. The schreibersite inclusion is darkened. (The position 

 of figure 4 is reversed.) 



161 



