176 CU. Shepard—Corundum of N. Carolina and Georgia. 
massive or crystallized however, it is readily cleavable ; and the 
crystals are remarkable for showing cleavage lines, whereby 
their faces are transversely ruled off into lozenge-shaped areas, 
often in a very beautiful manner. The prevailing colors are 
blue and red, the latter often of a deep tint and handsome. 
The blue is intense only in small patches, and shades off into 
gray or pale yellowish gray. Thus far I have seen no single 
remarkable for their translucency and internal regularity. Their 
unfitness for cutting, therefore, would appear to result from their 
too easy cleavage, rather than from other causes. The same crys- 
tal often combines the red and blue shades of color; the latter tint, 
if the form is pyramidal being the deepest at the base, and evin- 
cing a tendency to traverse the center of the crystal nearly to its 
apex, where the ruby color wholly replaces it, and sometimes 
here presents itself with much intensity. The faces differ con- 
siderably in smoothness and luster. Those belonging to the 
prism, the primary rhombohedron, and the face perpendicular to 
the axis, being the most perfect ; while those of the pyramids are 
the most deficient in finish. In size, the crystals vary from @ 
quarter of an ounce up to a pound in weight, though the latter 
are rare; while two have been foun 
comparative dimensions. It repre- 
sents them at about one-tenth the nat- 
ural size. 
The largest of the two is red at the © 
surface, but within of a bluish-gray. 
This was found by Col. Jenks last au- 
tumn at the Culsagee mine, Macon 
o., N. C.; and occurred in a layer of 
soft, almost pulverulent, vermiculite, 
within four feet of the surface of the ground. We undoubtedly 
owe the very perfect preservation of its form to the soft mater 
ial in which it was reposited. Had it occurred ata greater 
depth in the stratum, where the gangue is an unaltered ripido- 
lite, its extrication except in fragments, would have been impo> 
sible. The general figure is pyramidal, showing, howeveh 
scarcely more than a single six-sided pyramid, whose summit }§ 
