In all the rocks are talcose and show a
sort of conglomerate of quartz pebbles, in some cases water-worn and in
others angular, bedded in a mixture of quartz and granite detritus. This
has in the three areas undergone varying degrees of pressure, and has been
upheaved at different angles. In some cases the pressure and heat have
been so great that the rock assumes a distinctly gneissic character.
At Aji Bipa the lode runs N. 38? E. (Mag.) in the centre shaft, and N. 40
E. in the southern shaft, a sort of fault occurring in the centre shaft.
In the northern shaft I should put it at 38?, but from the way in which
the neighbouring rock had cleaved it was difficult to get the strike
accurately. The dip is the same in all three shafts, viz. 82?. The lode
being so near vertical, it can be clearly traced for the whole depth of
the shafts, and is very well defined. The hanging (eastern) wall is highly
coloured with iron oxides, and contains many quartz crystals which are
through-coloured with the same, and I do not think it at all unlikely that
garnets and other gems may be found in it. One or two minute crystals
showed a green colour, and might be tourmaline or emerald; but perhaps it
was only a surface-colour caused by the presence of copper.
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