M. FE. Wadsworth—Rocks of Newfoundland. 97 
diabase containing pyrites, and weathering brownish gray. 
Section greenish gray, and appears to, have been originally 
composed of divergent feldspar (plagioclase) with the inter- 
spaces filled by irregular grains and dissected masses of augite, 
magnetite, olivine (2), etc. At present the augite is in general 
only slightly altered, and is of a brownish color or nearly 
colorless. it is much fissured, sometimes cloudy and at others 
altered to a greenish chloritic material. The feldspars are for 
the most part kaolinized and oe Comptes retaining dis- 
tinct evidence of their triclinic charac 
Of secondary products there occur, sist others, considera- 
ble chloritic eas some calcite, quartz, microlites, and 
actinolite fibers.) A few greenish masses were seen that may 
e Ba cdbeior abe of olivine granules, their forms and polariza- 
tion characters being the same as those of such’ pseudomorphs 
seen in other basaltic rocks. 
At Tom Hall’s harbor, on Exploits Burnt Island, the main 
rock is a diabase cut by numerous later diabase dikes. The 
former (850) is a grayish green crystalline rock showing feld- 
spar and pyrite crystals. Under the microscope it is seen to 
be composed of divergent basaltic plagioclase with the inter- 
spaces filled by magnetite and secondary viridite, chlorite, and 
epidote. The feldspars are somewhat altered, although polariz- 
ing with brilliant colors, and contain epidote g granules, chlorite 
scales, and colorless needles resembling tremolite. e chlorite 
a short distance from this locality at Green Island Cove, 
€ prospecting had been done in a similar diabase rock con- 
Site some copper and iron pyrites. In the section the 
general structure of this (853) rock is seen to be the same as 
that of the preceding (850) but it has suffered further altera- 
tion so that the feldspars are considerably changed. Some 
calcite occurs in the rock. 
his rock is also cut by diabase dikes, one of which (851) is 
a greenish gray finely crystalline rock but more compact — 
the preceding and’ somewhat fresher. In the section it is seen — 
to be only a little less altered than No. 853. Considerable 
_ calcite and some greenish secondary eee was observed, 
_ otherwise the two.sections are nearly the sam 
Am, Jour, Paes deca Series, Vou. XXVIII, No. 164. ibis 1884, 
