Mining Operations in the East Ovoca District. 215 
ment, shown in cross section No, 2, has been called a “splice in the 
lode.” 
Yellow Copper Ore Lodes. 
The country rock for a considerable distance north and south of 
the main pyrites lode, in Tigroney and West Cronebane, is mine- 
ralized, containing finely disseminated particles of iron and cop- 
per pyrites, which on the surface have become oxidized, giving 
the decomposing rocks a burnt aspect; these rocks also bear 
evidence of metamorphic action. In these mineralized rocks, fora 
width of 25 fms. to the south of the main lode, the yellow copper 
ore lodes occur. As pointed out by Mr. Weaver, there are in these 
rocks horizontal joints (“beds or floors”) apparently unlimited in 
extent, some of which are open fissures two inches wide, others, 
again, are so close you could not insert the blade of a knife between 
the joints ; these “beds” generally occur at intervals of about 5 
fms. in depth, and are crossed nearly, but not quite, at right angles 
by a system of almost perpendicular joints, dividing the country 
rocks into huge rectangular masses. None of the copper ore lodes 
have gossan backs, but when one of these horizontal floors occurs 
at or near a copper lode, its back is filled with a sort of gossan 
made up of small fragments of the country rock cemented by 
oxide of iron and stained with copper. 
‘fhe yellow copper ore lodes are in general lenticular masses or 
cakes of ore apparently lying with the strike and dip of the 
“country rocks ;” these cake-like masses thin out in depth and 
length, and in places break suddenly into strings, some of which 
lead to other cakes. Sometimes, however, two or more cakes 
may be partly in contact, thus enclosing “horses” of the country 
rock, which have been cut away with the ore, thus leaving in 
the old workings spaces up to 10 fms. wide. In connexion with 
these cake lodes are caunter lodes; some of these occupy lines of 
fault which cross the country rocks nearly at right angles; a good 
example of this kind can be seen in the “ Grass level,” where the 
country rocks have a general strike of E. and W., and are 
crossed by a fault bearing N. 20° W. This fault in the “Grass 
level” is the western boundary of the dead ground between 
East and West Cronebane, and contains a 2-feet wide vein of 
rich chalcopyrite with a little quartz. Oftener, however, these 
