CORUNDUM IN UNITED STATES. 
129 
this vein continues as represented by the dotted line 3. Open cuts 
on the east and Avest side of this block of gneiss have followed border 
v^eins of corundum. PI. XVII, .1, gives a view of the peridotite 
formation near the cut on the east side. Little Avork has been done at 
Laurel Creek except on border veins, the principal exception being a 
small interior veni ((> in fig. 21) near the east end of the formation, 
from Avhich considerable corundum Avas obtained, but the A^in soon 
began to pinch out. PI. XVII, B, gives a vicAv of this vein, shoAV- 
ing both the hanging and foot Avails of peridotite. At 5, fig. 21, 
PERIOOTITE 
PAHTLY DUNITE 
Scale 
zoo 400 600 FEET 
COf^TOUR //^T£Rl/AL 20 r££T 
Fig. i'l. — Alap of the peridotite formation at I.aui-el Creelv, Kalnui County, Ga. 
considerable Avork has been done, and some large crystals, for Avliich 
:his mine is noted. Avere obtained here. 
This is perhaps the most famous corundum mine in this counti'y 
ind has furnished ore from Avhich an exceptionally good commercial 
product has been obtained. 
It has not been Avorked since 1891, Avhen the tunnels and shafts of 
he Big vein Avere cut off by the slipping of a large block of the 
)eridotite formation, nearly a 200-foot cube. It is that portion of 
he formation represented on the map (fig. 21) betAveen the open cut 
^1) and the cut to the AA^est of the block of gneiss (2). 
Bull. 269— 06 M 9 
