60 CORUNDUM^ ITS OCCURRENCE AND DISTRIBUTION. 
CORUNDUM IN CRYSTALLINE LIMESTONE." 
Extending from B_yram, Sussex County, N. J., to AVarwick Town- 
ship, X. Y., a distance of about 25 miles, there is a belt of limestone 
having a general northeast -south west strike, which widens out 
toward its northern end. Al^out 18t28 a specimen of sapphire corun- 
dum was found at Franklin Furnace in a detached piece of rock 
composed essentially of feldspar; but, although search was made, no 
more specimens Avere found in this A^cinity. A fe^v years later 
sapphire corundum Avas found in NeAvton ToAA-nship, about G miles 
from Franklin Furnace, embedded in a feldspar and partly sur- 
rounded by a carbonate. Prof. W. P. Blake ^ has described the 
occurrence of red sapphire corundum in the white crystalline lime- 
stones in Vernon ToAA^nship, Sussex County, N. J. The finest speci- 
mens AA^ere ruby-red in color, and the others Avere of A^arious shades 
of purple. The crystals AA^ere translucent, but no transparent ones 
AA'Cre observed. Dana reports the occurrence of sapphire corundum in 
these limestones near NeAvton and Yernon, Sussex County, N. J., and 
near Amity, Orange County, and Crugers Station, Westchester 
County, N.l\ 
The corundum found in these limestones of NeAv Jersey and Xcav 
York is near dikes and bosses of intrusive granite, and in the form 
of hexagonal crystals and irregular grains and masses of various 
colors — Avhite, blue, red, purple, etc. Associated with it are spinel, 
chondrodite, phlogopite, graphite, ilmenite, rutile, sphene, zircon, 
and many other minerals. The contact phenomena of the granite of 
Mounts Adam and Ea^c, in Orange County, N. Y., are described by 
Prof. J. F. Kemp and Mr. Arthur Hollick.^ Numerous silicates and 
other minerals occur in nodules or disseminated grains through the 
limestone, as hornblende, dark mica, augite, titanite, scapolite, pyrite, 
chondrodite, spinel, and fluorite, Avith occasionally sussexite, A^esu- 
vianite, tourmaline, and corundum. 
The crystalline limestones of Burgess ToAvnship, Lanark County, 
Ontario, Canada, also contain small grains and crystals of rose-red 
to sapphire-blue corundum in association Avith quartz, feldspar, cal- 
cite, muscovite, sphene, etc. 
Dr. A. Lacroix '^ has described the occurrence of corundum Avith 
liumite, brucite, amphibole, phlogopite, scapolite, spinel, sphene, 
rutile, zircon, and other minerals, in the marbles of Mercus and Ari- 
gnac, Ariege, France. Red and blue corundum has also been found 
associated with tourmaline in the dolomite at St. Gotthard; and the 
« Am. Jour. ScL, 1st ser., vol. 21, 1832, p. 319. 
" Idem, 2d ser., vol. 13, 1852, p. 116. 
"^ Annals New York Acad. Sci., vol. 7, 1893, pp. 638 et seq. 
'*Bull. Services Carte geol. France, vol. 2, No. 11; Am. Naturalist, 1891, pp. 138-139 
(Abst). 
