50 GOLD AND TIN DEPOSITS OF SOUTHERN APPALACHIANS. 
The country rock of this mine is amphibolite. Decomposition has extended below the 
present workings, but the true character of the rock can readily be discerned from the 
freshest rock in the bottom of the shaft. In the bed of the stream to the north also fairly 
fresh amphibolite is exposed. A number of interfoliated pegmatite dikes are seen at the 
creek. They are narrow, usually not over a foot in width, and suggest simultaneous injec- 
tion along planes of greatest weakness. This pegmatite is of the quartz-microcline variety, 
with only scattered small masses of compact muscovite. Near the bottom of the shaft the 
pegmatite becomes granitic in appearance. 
So far as known the dikes contain no tin where exposed at the creek. It is not even cer- 
tain that they are the continuation of the dike on which the workings are situated, but such 
is probably the case. The incline followed a southwestward-pitching ore shoot until the 
ground became so soft that the workings could not be maintained. Much of this ore was 
very rich, consisting of soft kaolin and a little quartz surrounding large and small masses of 
cassiterite. Groups of imperfect crystals and large irregular masses, some of which weighed 
as much as 100 pounds, were encoun- 
tered. The drift from the 75-foot level 
of the shaft is on the extension of this 
ore shoot. Here the percentage of tin 
is probably less, but the distribution is 
more even, rich pockets giving way to 
disseminated grains from the size of a 
walnut down. Near the end of the 
drift to the southwest the shoot passes 
below the floor of the level. The dike 
where cut by the shaft, at about 100 
feet, consists of a series of apparently 
disconnected lenses, many of them 
overlapping, which contain a little cas- 
siterite in small grains. (See fig. 6.) 
It is the intention to sink the shaft 
somewhat farther and then to turn a 
level southward in the hope of picking 
up the continuation of the ore shoot 
encountered in the workings above. 
It is almost certain that the float 
tin found in the soil on the slope be- 
low the shaft was derived from the 
upper continuation of this ore shoot 
above the present surface. Its low 
angle of pitch would on degradation 
allow the liberated fragments of cassi- 
terite to cover a considerable horizontal 
strip with but little lateral transportation. It is doubtful if the quantity of float tin found 
will be very great. In fact, it seems probable that the greater part has already been removed. 
It is difficult to estimate the percentage of tin in the ore because of the variable content 
of cassiterite in different parts of the dike and the ore shoot. A 100-pound sample across 
the dike at the ore shoot on the 75-foot level was washed and gave 9 pounds of cassiterite, or 
about 6.5 per cent metallic tin. This is probably somewhat better than the ore shoot will 
average. Outside of the ore shoot the quantity of cassiterite in the dike is very small. 
Water has been a troublesome factor in the sinking of the shaft and pumping is con- 
tinued day and night. 
One carload of nearly 20 tons of concentrates was shipped to England from the Ross 
mine in 1903. Another carload, bringing the total shipment to about 75,000 pounds, was 
sent out in 1904. Several thousand pounds are now on hand ready for shipment. The 
average content of these concentrates was about 66 per cent metallic tin. 
Pegmatite Amphibolite 
Fig. 6.— Diagram of pegmatite dike of the interfoliated 
type, Ross mine, 75-foot level, showing extreme irregu- 
larity of structure. 
