52 CORUNDUM, ITS OCCURRENCE AND DISTRIBUTION. 
diameter in biotite-gneiss. The nodules are often drawn out into 
small lenticular " eyes." The corundum is chiefly confined to the 
micaceous bands of the gneiss, and, on account of the greater resist- 
ance of its muscovite coating, it stands out in prominent knobs over 
the weathered surfaces of the gneiss. A similar occurrence is found 
in the gneiss at the mouth of the North Fork of Ellijay Creek, in 
Macon County. Also, 3 miles north of this, corundimi is found in a 
decomposed hornblende-gneiss on the summit of Turkey Knob. In 
this same general vicinity corundum has been found in chlorite- 
schist, as described on page 59. 
Six miles southeast of Burnsville, Yancey County, N. C., on Celo 
Ridge, near South Toe River, corundum is found in almost the same 
relations as described on page 118 on the mountain north of Corun- 
dum Hill mine. An enstatite rock partly altered to talc appears in an 
outcrop about 50 feet wide. Along its eastern border some chlorite 
is developed, and in the adjacent decomposed gneisses corundum is 
found for a distance of 2 or 8 feet from the contact. The corundimi 
is in irregular masses and imperfect crystals up to 2 or 8 inches long, 
and is often more or less inclosed in radiating muscovite. 
Corundum occurs in decomposed gneiss associated with no other 
recognizable rock three-fourths of a mile northwest of Bakersville, 
Mitchell County, N. C., on the Johnson road. So far as could be 
ascertained, the conditions here are very similar to some of those on 
Shooting Creek, in Clay County, already described. 
At Corundum Hill mine, Macon County, N. C., one of the chief 
sources of corundum has been the peripheral or border vein developed 
along the southeastern border of the peridotite. (See map, PL XV.) 
When this mine was visited, in 1895 and 1896, the tunnel following 
this vein had encountered a tough hornblende rock in the gneisse^^ 
adjoining the peridotite, varying in character from a hornblende- 
gneiss to a massive amphibolite and bearing corundum in consider 
able abundance in grains and small crystals. At the time mentionec 
this material was one of the principal sources of corundum, the rod 
being blasted out and hauled to the mills on wagons for crushing anc 
cleaning. The exact nature of this rock is in doubt. The peridotit< 
is everywhere bounded by biotite-gneiss and mica -schist, so far a; 
appears at the surface ; but as bands of hornblende-gneiss frequentb 
iippear in the biotite-gneiss it might very well be a hiember of th< 
gneisses proper. On the other hand, its occasional massive characte 
and its abundance of corundum make it closely resemble the amphib 
olites that form dikes in and about so many of the peridotites ii 
Clay County and the adjoining portions of Georgia. 
On top of the mountain spur 2 miles north of the Corundum Hil 
mine, Macon County, N. C, an outcrop of enstatite-talc rock abou 
50 feet wide occurs. The partly decomposed, friable gneisses at th 
