1893. ] NEW YORK ACADEMY OF SCIENCES. 87 
Igneous granite or related rocks outcrop at many points in 
the white limestone near Franklin. A great intrusoin was cut 
some years ago in the Trotter Mine, and it lies on one of the 
dumps still. It isa green granite with finely bounded crystals 
of amazon stone in great aboundance. In thin section it ex- 
hibits, microcline, orthoclase, considerable hornblende and at 
times is very rich in allanite. It is a basic granite and is poor 
in quartz. The earlier descriptions speak of outcrops of ‘‘sien- 
itic”’ granite near the vein and in the limestone to the eastward 
of this point (Nuttall, p. 243) and on the large map of the re- 
port of the New Jersey Survey, 1868, a pink gneissic or granitic 
mass is colored in just east of the location of the Trotter Mine. 
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Fie. 7. Section CC. oF Fie. 4. 
This still can be seen and is a well known locality for garnets 
although the character of the rock is less clear than the granite 
inthe mine. A great dike of granite appears in the quarry, just 
southwest of the furnace. It consists of quartz, microcline 
biotite and a little plagioclase. Still further south at the aban- 
doned iron mines, dioritic facies appear and coarse pegmatites, 
with masses of colophonite, coccolite, and other interesting 
minerals that led Prof, Groth, of Munich, whom I had the honor 
to conduct over the region, to call it at once, “klein Arendal,” 
so close is the parallel with the famous Norwegian locality. 
