ON THE RUBIES OF BURMA AND ASSOCIATED MINERALS. 
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(b.) Minerals which occur in the limestones, but have not been found in the masses 
with which the limestones are interfoliated. 
There are a few minerals (which must be relegated to a third group, as they occur 
rarely in the pyroxene-gneisses and pyroxenites, but are much more abundant in the 
limestones. 
Belonging to the class (a) are the following species :— 
Diopside (white and pale-green). 
Bright-green augite. 
Purplish-brown augite, passing into diallage and pseudo-hypersthene. 
Sahlite (white, aluminous augite.) 
Enstatite. 
Bronzite. 
Hypersthene. 
Quartz. 
Orthoclase (Murchisonite and Moonstone). 
Oligoclase. 
Anorthite. 
Hornblende (a variety near Basaltic Hornblende). 
Biotite and other micas, including Fuchsite. 
Scapolite. 
Zircon. 
Magnetite. 
Titan oferrite. 
Sphene (both original and secondary). 
Rutile (in inclusions). 
Garnet (almandine). 
(6.) Among the minerals which especially characterize the limestones are the 
following :— 
Phlogopite (changing to vermiculites). 
Wollaston ite. 
Corundum (ruby). 
Spinel. 
Pyrrhotite. 
Diaspore. 
Hematite. 
Limonite. 
Apatite (Moroxite.) 
Graphite. 
The minerals which occur in the gneisses but have not certainly been detected in 
the limestones are :— 
Tourmaline (Rubellite, Indicolite, &c.). 
