272 Jfoftrfi — 7'ei<ts ujwn the Synthetic Sapphires of Verneuil. 



The t'ollowiiiaj physical and crystallographic characters were 

 detei'iiiiiRHl bv me : 



ILd'ilness 9, that is less than that of carborundum, greater 

 than that of chrysoberjl and not noticeably diiferent from 

 that of the natural sapphire. In grinding it was very little 

 affected ])y emery. 



Specific gravity as determined upon one polished fragment 

 of the cone and upon two of the cut stones. 



Cone 3 988 



Cut stone 4'01 



Cut stone 3-977 



Natural sapphire is stated b}' Bauer (Edelsteinkunde, p. 319) 

 to have the specific gravity of -i'OS. ' 



Fig. 1. 



^^^^^^^^^^^^^^^^Vi "^'''^^^IP^ 



p 



1 



^■l 



^k 







,,.J^" 



* 



Parting. Although the finely crushed fragments of the 

 cone examined under the microscope showed in general only 

 irregular to conchoidal fracture, some of the particles showed 

 a development of sets of parallel-plane separations at angles 



