DESCRIPTIONS OF TIN MINES. 49 
Along this crosscut are seen several unimportant faults, probably of small throw. As the dike 
is approached the schist contains many narrow white streaks, a few millimeters wide, which 
prove to be decomposed dikelets of pegmatite injected parallel to the foliation of the schist. 
At the crosscut the dike is about 3 feet wide, but broadens along the drift to the northeast, 
and soon reaches a width of 13 feet. This is known as the west dike. A crosscut 21 feet 
east from the bottom of the shaft discloses another dike of pegmatite, 3 feet wide, nearly 
vertical, and striking about N. 5° E. This is called the east dike. A drift which follows it 
northward for about 55 feet shows that it widens to about 12 feet. At the north end of the 
drift the dike appears to be pinching out and pitching downward toward the north. At 
this poin a crosscut from the east to the west dike shows that they are 33 feet apart. A 
continuation of the northeast drift on the west dike discloses what appears to be the junction 
of the two dikes, but work was abandoned before this point was settled. 
All the pegmatite seen underground is much decomposed. The feldspar and mica 
apparently both alter to kaolin and silica, causing the dikes to be soft and easily worked. 
The east dike contains several large masses of this mixture of kaolin and silica which repre- 
sents feldspar. Remains of the feldspar cleavage are preserved in many places and show 
that some of the individuals were large, reaching a breadth of several centimeters. These 
masses were probably segregations of feldspar. They are balanced by lense-like masses of 
quartz, many of which are more than a foot in length and some of which reach a foot in 
width. This was apparently a very coarse-grained portion of the dike. The west dike 
contains many small black particles readily mistaken for cassiterite, but they are soft and 
can be easily crushed to a dark-brown powder. They are undoubtedly the alteration 
product of lithiophilite. Purpurite (see p. 38) is associated with the black material in 
some places. 
Cassiterite is present in grains of small size sparingly scattered through portions of the 
west dike. Larger and more abundant particles of the mineral were found near the north- 
east end of the drift on the west dike. This richer portion appears to be a shoot pitching not 
very steeply to the northeast. It is probable that this is the continuation of the shoot 
exposed on the surface near the shaft. The percentage of cassiterite, even in the shoot, 
however, was not considered sufficient to warrant further expenditure, so operations were 
suspended. Water was never encountered in this mine. 
To the south and southwest of the shaft several pits have reached pegmatite dikes. 
Some of these contain such a percentage of tin as to appear worthy of further development. 
ROSS MINE. 
This mine, located on the property of Capt. S. S. Ross, is about 1J miles northeast of 
Gaffney, S. C. It is at present being worked by the owner. Fragments of cassiterite were 
discovered in the soil early in 1902. Search showed a considerable quantity present on the 
slope toward a small stream which crosses the property. Considerable of the soil on this 
slope was sluiced and much of the cassiterite saved. As progress was made southward up 
the slope tin ore was found in place in compact reddish clay, which changed to white a 
short distance below the surface. This clay proved to be the decomposed outcrop of a tin- 
bearing pegmatite dike and attention was then directed to the deposit. A trench showed the 
course of the dike to be N. 48° E. and its dip 60° to 65° SE. An incline pitching at a low 
angle was run southward for 135 feet. About 25 feet south of the projection of the bottom 
of this incline a vertical shaft was sunk on the hanging-wall side of the dike. This shaft 
cuts the dike at about 100 feet below the surface. At a depth of 75 feet a crosscut west 
from the shaft reaches the dike in 30 feet, and drifts about 30 feet long have been run along 
the dike in each direction. Sinking of the shaft is now being continued. The surface 
developments include a shaft house, two large boilers, and a steam hoist recently installed. 
A near-by stream has been dammed to furnish a sufficient quantity of water for washing and 
sluicing the ore. 
Bull. 293—06 4 
