J30 NEPHRITE AND JAUEITE. 



3e8 a do value whatever in the work of tracing the migration and inter- 

 commaui cation of races lies in the fact that these substances are com- 

 oaratively common constituents of metamorpbic rocks and hence liable 

 J,', be found anywhere where these rocks occur. Their presence is as 

 meaningless as would be the finding of a piece of graphite. The natives 

 required a hard, tough substance capable of receiving and retaining a 

 sharp edge and polish, and look it wherever it was to be found. 



Explanation of Plate-Microstructvre of Nephbite and Jadeite. 



Fig. 1. Nephrite, New Zealand t" 



2. Nephrite, Alaska i 



:?. Nephrite, Liberia ^ 



4. Jadeite, Oaxaca, Mexico ¥ 



