184 J. L. Smith—Corundum of North Carolina, ete. 
Diaspore.—While this mineral is found so abundantly with 
the corundum of Chester, Mass., I have not been able to find it 
with the North Carolina corundum. Several specimens of sup- 
posed diaspore have been submitted to me, but on close exam- 
ination it was found to be colorless cyanite 
Chlorite.—This mineral abounds in this locality, and, as has 
been stated, is the gangue-rock of the corundum; it not only 
surrounds the corundum, but permeates it. ere are several 
varieties, varying in color from a yellowish- -green to a dark- 
green, and differing a little in composition. Two specimens 
om the same locality were composed as follows 
Large plates. Friable. 
Peer Se a EE 27°00 29°15 
Alege. of oSOlY Los SS. 21°60 10°50 
Oeise of Woo, 25) oe Sc. 16°63 23°50 
Magnesia Sire SEO 25°44 
Weaher ses 050 bo oy etuia gt 1 ESRO 10°04 
e . localities is abundant mixed with the associated 
frinicnal Chemical analysis was made of a specimen with 
the following result: 
ORs oi eek eee 32°41 
Alumina 51°31 
HAG ls 10°98 
OT SIREIARIE ce es iG BAN Ts lS 2°43 
8 Sa a Se Re 2°13 
Zoisite.—This mineral occurs in two forms—a black ae 
and a light-green variety. These minerals have been called by 
some Arfverdsonite, but neither of them have the composition 
of that mineral. Their compositions were as follows: 
Lake Geneva. Black variety. 
9 4 
Mek A Pea SS 45°70 43°5 5°90 
Alenia so 6 gonb0 24-01 27°72 13°34 
a of ivonicc.2 2: 4°56 2°61 11°46 
13°44 21°00 19°20 
Proareliaas ne ee 8:03 2°40 pote 
i ad wnin sale gad gic 2°91 3-08 3°39 
Wat 60 oe 66 
Oxide. of chrome___-_-. 52 in gh a--- 
The green variety has a very pale chrome-green color; for 
comparison the analysis of a similar specimen from Lake 
Geneva is annexed. 
