114 THE GRANITES OF MAINE. 
The quarry, opened recently, measures 50 by 25 feet and 5 feet in 
depth. The sheets, from 2 to 5 feet thick, dip 20°-30° W. Vertical 
joints strike N. 25°-30° E. There is one derrick. 
The Pettee black-granite quarry is three-fourths mile north of 
East Sullivan, on the road to Tunk Pond. Owner, J. A. Pettee, 
East Sullivan. 
This rock (specimen 80, b) is a mica-quartz diorite of very dark 
gray shade and fine to medium texture with occasional porphyritic 
whitish feldspars up to one-fourth and more rarely one-half inch. 
It consists, in descending order of abundance, of white translucent 
soda-lime feldspar (oligoclase-andesine), black hornblende, opales- 
cent quartz, black mica (biotite), and magnetite, together with acces- 
sory titanite, apatite, and pyrite. It takes a fine polish, and the 
contrast between polished and cut surfaces is marked. The diorite of 
East Sullivan is referred to by W. O. Crosby in a paper on the 
Geology of Frenchmans Ba} 7 .° 
The quarry, which is only 15 by 15 feet and 8 feet deep, is on the 
west side of a knoll 20 to 25 feet high. 
Rock structure: Vertical joints striking N. 25° W. and N. 85° W. 
recur at intervals of 1 to 5 feet. The rock splits in these directions 
also horizontally. There are whitish bands or veins one-half inch 
thick, consisting almost entirely of the feldspar and quartz. 
This stone is quarried occasionally in small blocks for monumental 
purposes. 
The Sinclair black-granite prospect is 1J miles north of East Sul- 
livan, on Herbert and Thacldeus Sinclair's (formerly Smith Bean's) 
farm, near Charles Dowel's sawmill. 
This rock (specimen 82, a) is a quartz monzonite of almost black 
shade, with white blotches, of medium to coarse (porphyritic) tex- 
ture, consisting, in descending order of abundance, of bluish opales- 
cent quartz, whitish soda-lime feldspar (oligoclase-andesine), and 
potash feldspar (microcline and orthoclase), black hornblende, and 
black mica (biotite), together with accessory magnetite, pyrite, titan- 
ite, and apatite. Some of the feldspars measure nearly an inch in 
length. This is closely related to the true granites, as it contains 
nearly as much potash feldspar as soda-lime feldspar, although it is 
among the darker of the " black granites." 
The ledge is exposed for a length of 50 feet north-south and a 
height of 20 feet. A vertical joint strikes N. 20° W. An opening 
10 by 5 feet and 5 feet deep was made here in 1902. 
The Baird quarry is on Swans Island, east side of old harbor, not 
quite 1 mile east of Swans Island village and three-fourths mile 
southeast of Mintum. Operators, The Mathew Baird Contracting 
Company, 433 East Ninety-second street, New T York. 
a Proc. Boston Soc. Nat. Hist., vol. 21, 1880, p. 110. 
