Plate 27 



1. Kloxdike, Yukon. Canada; nickel-rich ataxite; Xi-Co 19.11 percent. General struc- 

 ture, kamacite bodies in a dense, inperfectly granular groundmass. The minute kamacite 

 spindles and needles are thickly disseminated, almost invariably inclosing droplike inclusions 

 of phosphide eutectic. Occasionally the needles are long and thin and a few reach a consid- 

 erable size, large enough to extend across a field of the size and magnification of this figure. 

 Picral 25 seconds; X 60. U^S. National Museum. 



2. Klondike. Part of the groundmass with four minute kamacite bodies. The predom- 

 inant clear white is taenite. The kamacite shows slight darkening from gamma admixture. 

 The plessitic areas show an aggregate of kamacite particles in taenite, the kamacite particles 

 scanty, minute, and irregularly scattered. Picral 5 seconds; X 600. 



3. Klondike. One of the larger kamacite spindles at higher magnification, with iron- 

 phosphide eutectic inclusions, surrounded by taenite which merges with the taenite of the 

 groundmass. The kamacite shows some admixture of minute gamma particles. The pat- 

 tern of the groundmass suggests granulation, perhaps owing to phantorn boundaries of forme 

 gamma grains. Picral 25 seconds; X 120. 



4. Klondike. The same area as figure 3, with additional sodium-picrate etching. The 

 iron-phosphide areas are blackened, but the rest of the structure is unaffected. Picral 25 

 seconds and neutral sodium picrate; X 120. 



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