CATALOGUE OF GEMS. 



525 



Rose quartz. — ^Rose to pale pink, iiioie or le.ss tninsparont. and usually 

 massive. Luster, vitreous, occasionally oroasy, and sometimes opal- 

 escent. Rose quartz is liable to lose its color on exposure to light. 



Sagenitic (puirtz. — Quartz penetrated with acicular crj'stalsof other 

 minerals, as rutile {Venus hair stone or jiecJie (Vamour) hornl)lende, 

 tremolite, actinolite {Thetis' -Jiair stone), gothite, tourmaline, etc. (Plate 

 7.) Chlorite in quartz is common, and advantage is often taken of its 





presence in working up the specimen. Gold, silver, copper, etc., are 

 frequent inclusions, and such specimens are largely used in jewelry. 

 Often the included mineral is so a))undant that the quartz is present 

 onl}' as a cementing material. An example of this is set'u in the 

 erocidolite quartz or tiger-eye. 



!Saj>2^hirine or siderite. — A translucent, indigo, Berlin, or pale gray- 

 ish blue, vitreous quartz. 



