302 BROWN A HERON: GEOLOGY WD ORE DEPOSITS <>K TAVOf. 



rngersol] machine driven by an oil engine. An aerial ropeway 

 connects Anauktaung with the mill, 



On the Aletanng section there are at least live veins in granite, 

 varying from 3 to 5 feet in thickness, which have been traced lor 

 over 1.000 feet each in strike extension. Their general strike 

 is north 11° east, south 11° west and the dip about 65° easterly. 

 These veins are being developed by drives From their northern 

 ends at about GO feet vertical intervals. The section is connected 

 to the mill by a tramway. 



On the Shamatanng section two veins are being developed by 



drives 280 feet vertically below their outcrops, while a number of 

 veins on the Kalataung are to receive attention in the near future. 

 The residual surface deposits are hydrauliced by a number ot 

 monitors working under heads of 300 to 400 feet. These operations 

 can only be carried on during the rainy season when an abundant 

 water supply is available. 



The mill contains the latest machinery for crushing, concentra- 

 tion and recovery from slimes. Power is supplied bv a 50 h. p. 

 semi-Diesel engine. At the time of writing. May 1919, the mill 

 was nearly completed but crushing had not commenced. 



Pyrite is the commonest associated vein mineral and the portions 

 of the veins within the oxidised zone are stained black and brown 

 by the decomposition of this and other minerals. The vein quartz 

 is of a solid, vitreous variety tending to separate into great, cubical 

 blocks. Small, imperfect vugs and hollows filled with black iron 

 and manganese oxidation products, decomposing pyrite crystals 

 and traces of sulphate of iron are common. 



The decomposition of the Aletanng granite has been excep- 

 tionally profound and the rock in situ is often quite soft to over 

 100 feet from the surface. When fresh it is a tough, white variety 

 with more muscovite than biotite but, when oxidation sets in, it 

 becomes red and mottled red and white. Seams and films of kaolin 

 up to I of an inch in thickness then often pierce it. The veins 

 themselves are always bordered with well developed greisen bands 

 and thin zones of green mica-rock traverse the greisen. Occasion- 

 ally the granite has been greisenised in patches and irregular masses 

 which do not contain vein quartz, and it is difficult to resist the 

 conclusion that this is due to some form of gas action, in the latter 

 stages of its formation. On Anauktaung also the sedimentary 

 capping carried a three-foot band of greisen, parallel to the flat 



