212 BROWN & HERON: GEOLOGY AND ORE DEPOSITS OF TAVOY. 



of the mine, to whom we are indebted for specimens. These are two 

 broken crystals of a beautiful translucent pale amethystine blue 

 colour exhibiting the pyramidal faces. Both crystals are about 1 

 inch in length and it is curious to observe that certain faces are 

 covered with a secondary crust of the same mineral, } inch in thick- 

 ness and of a lighter tint. 



Since then other specimens have been found in situ, and small 

 amounts of scheelite can be picked out of the coarse jig concentrates 

 from time to time. 



The first consist of irregular pieces of a creamy yellow variety 

 occurring in a pegmatite with wolfram, brown cassiterite, pyrite 

 and pale green and colourless fiuorite ; small flakes of molybdenite 

 are intergrown with the green mica of the" walls. The colourless 

 fiuorite contains hair-like inclusions of a black mineral which recalls 

 some forms of bismuthinite and has not been determined. 



The second, i.e., the jig product, is either white, grey, straw-yellow 

 to pale brown or pale translucent blue. Fragments of crystals and 

 pieces intergrown with wolfram are common. 



Scheolite also occurs in a wolfram-bearing lode on Mr. T. Fowle's 

 Yanmazu North mine. Here it is usually of an opaque white colour 

 stained and discoloured brown by iron compounds. Some fractured 

 surfaces when examined at the proper angle show the cleavage 

 planes. Polished specimens exhibit creamy yellow scheelite and 

 felted masses of fine acicular wolfram. The latter is in no way 

 intergrown with the scheelite, which appears to have been deposited 

 later than the wolfram, and indeed- than part of the quartz, as 

 hexagonal- outlined sections of the latter can be found surrounded 

 by scheelite, which also fills in the angular spaces between the long 

 quartz crystals. 



Opaque white scheelite is also known intergrown with massive 

 wolfram, where it occupies spaces between the individual crystals. 

 Specimens of this kind from the Zinba mine have been presented 

 by Dr. J. Morrow Campbell. They also contain interspersed pyrite 

 and quartz, while a scaly form of molybdenite is coated on the 

 outside, nearest the wall of the vein. 



Thin tablets of a pale greenish-yellow scheelite occur in a line 

 greisen which also contains wolfram, molybdenite, chalcopyrite, pyrite 

 and bismuthinite from the same locality. 



The larger pieces of scheelite, where they outcrop in veins, 

 can readily be mistaken for quartz, and it is almost certain 



