COLOSSUS GOLD MINE. 89 
The fact that of the ore milled during the former working of the mine a large percentage- 
was not recovered is to the writer's mind an indication that considerable of the gold was 
contained in pyrite. On many of the numerous minor joints flat scales of pyrite occur, 
some of them with a rudely radiating structure. These fractures and the pyrite in them 
have almost certainly been formed subsequent to the principal deposition of quartz and 
sulphide. This occurrence of pyrite is rather common in or near the porous rock from 
which pyrite has been removed and is perhaps a redeposition of the actual material which 
constituted the original pyrite crystals. Where oxidation has been marked, small flakes 
of gold are frequently found on joint faces, only loosely attached to the rock and presenting 
the appearance of having been derived from this probably secondary pyrite. If such is the 
case it would seem to argue in favor of secondary enrichment, or at least solution and 
redeposition of gold comparable to the secondary enrichment of copper. 
The ore which has been mined from the Colossus mine has probably been of higher grade 
than that taken from the Haile mine. That near the surface was rich, some of it running 
over $200 per ton.« In the later work the ore is said to have averaged about $15 per ton.b 
The tailings recently worked by cyanide had doubtless been subjected to some concentra- 
tion by the action of the water which discharged them from the mill and by subsequent 
rains. They are said to have yielded from $3 to $15 of gold per ton. These values are 
not justly comparable with those at the Haile mine, for there the bodies of ore worked 
have been extended to the greatest possible size by including rock of lower and lower grade, 
while up to the present only the richer shoots, much smaller in size, have been mined at the 
Colossus. Assays made by the present company are said to run from $2 to $2,000. The rock 
broken in sinking the Pansy shaft is said to have averaged $8. As this is near the middle 
of what is considered the ore body, it is probable that the average value of the deposit 
will run somewhat under that figure. Lieber, writing in 1856, c states that the gold was 
worth 87^ cents per pennyweight, which, on the assumption that the accompanying material 
was silver, would make the fineness of the gold about 0.840. Of the $36,000 extracted 
by cyanide, about $1,100 is said to have been silver, making the fineness of the gold recov- 
ered from the old tailings about 0.435. It is stated by Professor Hanna, who made many 
assays of this ore, that the fineness ranged from 0.725 to 0.775.^ 
The old stopes are not extensive. A chimney-like ore shoot in the Bull Face workings 
was followed by the incline shaft. It pitches about 75° NE. At a depth of 140 feet the 
stope on this ore shoot is 20 feet wide and 40 feet long. From 140 down to 220 feet the 
stope ranges from 20 to 30 feet in diameter. Below that depth — the water level at the time 
the mine was visited — the size of the stope was not known, although it is said that when 
the old work was stopped there was ore in the bottom of the shaft and ore was left on the 
northeast side of the stope. The value of the rock forming the walls of this old stope was 
not learned by the writer. Of the stopes in the other old shafts practically nothing is known 
at present. They probably followed shoots similar to that in the Bull Face. 
The Colossus Company has control of 10,000 feet along the strike of the deposit, and gold 
is known to occur at intervals throughout this extent, but adequate prospecting has been 
done on very little of the property. The portion which the company expects to mine at 
present is said to be 400 feet wide and perhaps 800 feet long. This body, approximately 
vertical, is parallel in its long direction to the foliation of the schists. At the bottom of 
the Pansy shaft crosscuts in each direction have been run about 100 feet. They show 
narrow strips of soft, almost barren rock, which separates zones of ore, but which are of 
so small bulk that it is the belief of the company that the whole may be mined and milled. 
In the writer's opinion — based, it is true, on a hasty and superficial examination of the 
deposit — exploration has not yet been sufficient to warrant so extensive preparations for 
milling as are being undertaken. It is questionable, moreover, if the straight cyanide 
process to be employed will sucessfully treat this sulphide ore. 
a Emmons, E., Geol. Rept. Midland Counties of North Carolina, 1850, n. 1314. 
&Cf. Nitze and Hanna, Bull. North Carolina Geol. Survey No. 3, 1896, p. 105. 
c Op. cit., vol. 1, p. 57. 
d Kerr and Hanna, Ores of North Carolina (chap. 2 of Geology of North Carolina, vol. 2) , 1893, p. 235. 
