Plate 44 



1. Cleveland, Tennessee; medium octahedrite; Ni-Co 9-10 percent. Irregular plessite 

 inclusipns. The lamellae of taenites are dark because of supersaturation with respect 

 to kamacite; the triangular areas above and below have incompletely transformed cores 

 with an acicular gamma-alpha structure. Picral 50 seconds: X 60. 



2. Odessa, Texas; coarse octahedrite; Ni-Co 7.99 percent, P 0.23 percent. Irregular 

 plessite field bordered by dark supersaturated taenite; within, needles of kamacite and a 

 dark untransformed area. Two small clear Schreibersite bodies and two irregular larger 

 ones with black marks due to chipping. Nital 10 seconds; X 60. 



3. Otumpa, Argentina; hexahedrite; Ni-Co 5.68 percent. Plessite consisting chiefly of 

 needles and granules of kamacite. Other plessite fields in great variety are found in this 

 iron. Otumpa was classified by Brezina and by Cohen as a nickel-poor ataxite, and it is 

 still so listed in all museums. It is, however, a granular hexahedrite, in many places with 

 a profusion of Neumann lines, which often run parallel through several grains. Rhabdites, 

 and needles and irregular bodies of schreibersite, are abundant. Light picral; X 30. 



4. YouNDEGiN, Australia; coarse octahedrite; Ni-Co 7.01 percent. A plessite field with a 

 well-developed but irregular pearlitic structure. Picral 10 seconds; X 60. 



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