Metamorphised Balmville limestone with visible phlogopite crystals. Also contains tremolite visible at the outcrop level. Within nose of anticline of Walloomsac schist.
The PPL thin section shows a large irregular calcite grain with tremolite at…
Metamorphised Briarcliff dolostone with visible micas. Contains diopside, tremollite, and phlogopite. At the metamorphic grade of the first sillimanite isograd.
Thin section shows irregular dolomite grains in the center, with pleochroic…
Schist with coarse biotite controlling foliation. Garnets visible in some hand samples. Kyanite blades without preferred orientation--at higher concentration within folds. Possibly from the Walloomsac schist.
Metamorphised sandstone with a gray, glassy appearance. From the Paughquag quartzite, a late Cambrian formation. The basal Cambrian quartzite rests on pre-Cambrian gneisses.
The thin section shows quartz and plag with some biotite and grain…
Schist with coarse staurolite grains. This outcropping is approximately on the strike of the chloritoid schists (sample 7). Also contains garnet, muscovite, feldspar, and quartz. Presumed to be from the Everett Schist.
Schist bearing both staurolite and chloritoid. This marks the first appearance of staurolite in the metamorphic sequence. Also contains garnet, muscovite, chlorite, biotite, feldspar, and quartz. The assemblage in not in equilibrium.
Schist with coarse chloritoid crystals (up to 1/8 inch) without preferred orientation. These crystals grow across the foliation developed in the schist, but appear deformed. Chloritoid is a silicate mineral made in metamorphism. It also contains…
A highly graphitic slate in the Walloomsac slates. Contains pyrite. This rock also contains biotite, chlorite, muscovite, quartz, ilmenite, and pyrite.
The thin section shows large biotite grains, and chlorite muscovite, and quartz. Fluid…
The graywacke facies in the Mt. Merino member (where sample 4 also comes from). Graywacke is a hard, dark-colored sandstone. This sandstone represents a similar rock to the protolith for the quartzite of sample 10.