CuAV. XXXVI.] 
NAOPTTU : LOITDONOni. 
915 
beds may be about 60 feet, but it is impossible to estimate this with any 
accuracy. Its limits are obscured on all sides by talus-oro, but the breadth 
of the ore-body near the surface is probably not nmch greater than the 
actual breadth exposed in the workings, which is about 110 yards ; for tho 
ore-beds at both the north and south boundaries are dipping ste^'ply, 
with practically no overlying layers to be accounted for. 
The immediate ' country ' of the ore-body was not exposed in Feb- 
ruary 1904, nor even in December 1906 ; but two pits dug to the north 
of the ore-body showed a coarse muscovite- pegmatite containing deep 
violet-blue to violet-black tourmaline. 
By my third visit — December 1907 — however, the rock underlying 
the ore-beds had been exposed. It was the usual mica-schist with some 
associated quartzite. In another place a 1-foot parting of mica-schist 
in the ore-body had been exposed. 
A very large proportion of the ore-body consists of manganese-ore, 
but there are a few layers of various quartzites, the varieties seen being 
dark-grey coarse-grained vitreous, white vitreous, and grey sandstone- 
like, quartzites. Some layers are composite. That is, one side of the layer 
may consist of braunite and psilomelane whilst the other is quartzite, 
there being a passage from one to the other in the interior of the layer. 
There are also, in various parts of the deposit, irregular veins of quartz. 
At the very east end of the south part of the quarry the ore is 
sometimes fluted parallel to the strike, this being, probably, a sort of 
slickensiding phenomenon. 
At about the point A 
there was exposed, along 
a joint plane roughly at 
right angles to the strike, 
the section illustrated in 
figure 67. The orei-beds 
thus folded were a little 
shattered, and very much so 
in the middle of the fold. 
Along the quarried wall of 
manganese -ore at B there 
was a considerable quantity 
of vein- quartz (?) in the 
manganese- ore. At C, the 
section from the south edge 
of the deposit to the fold- 
X 
S.8°W. 
Fig. 67. — Diagram of a fharp fold in the manga- 
nese-ore layers at Lohdongri. 
IV 
