1889. ] NEW YORK ACADEMY OF SCIENCES. 59 
dant in shaft No. 1. The perfect crystals are generally of a 
dark-green color, and measure from 15 to 42 mm, in length. 
The planes observed are I, i-i, O. 
A variety of pyroxene from the deeper workings is pyrallolite, 
which occurs massive, of a light-pink color; also occasionally 
radiated. 
Amphibole, Byssolite. Besides the common byssolitic calcite 
there is a more perfect form, in which the calcite has been dis- 
solved, leaving the crystals in beautiful slender needles, many of 
which are 42 mm. long. 
Actinolite also occurs here in radiating crystals. 
Erythrite is disseminated throughout the byssolitic rock, and 
associated with calcite in Shaft No. 1; lustre very dull. 
Aragonite occurs at Shatt No. 1, in silky fibres and acicular 
erystallizations. It is, however, not equal to that from the 
Jones Mine, a few miles north in Berks County, which is noted 
for its beautiful aragonite. 
Magnetite is found abundantly in small brilliant octahedrons. 
Garnets. Lime-iron garnets in dodecahedral crystals of a 
brownish-black color occur in considerable quantities at Shaft 
Das-1. 
Dana mentions aplome garnets as occurring here, which I 
think is erroneous, as I have never noticed any striations what- 
ever. 
acht : i i i 
Malachite a either massive or coating the other min- 
Chrysocolla ¢ vals, particularly the calcite. 
Bornite 
Mr. Georce F. Kunz read the following paper: 
A REMARKABLE LOCALITY OF AMERICAN FLUORITE. 
About four years ago, asmall vein of fluor-spar was discovered 
in the town of Macomb, St. Lawrence Co., N. Y. It was 
worked from time to time until last summer, when the vein 
suddenly widened, breaking through into a cavity or cave, which 
proved to be sixteen feet in length, and ten feet in width at the 
narrowest part, widening out to fifteen or eighteen feet or more. 
The top, bottom, and sides were lined with a magnificent sheet 
of crystals, varying from one to six inches in diameter, each in 
turn forming part of larger composite crystals. Between the 
floor and the walls was a layer of partly decomposed calcite, 
readily removable, so that groups of fluor-spar crystals, weighing 
from ten to several hundred pounds each, and in one case 
measuring two by three feet, were easily detached. The cavity 
contained at least fifteen tons of fluorite. 
The habit of the crystals, in almost every instance, is that of 
