What type of rock is this? What unit is it a part of? 

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A small diagram showing the stratigraphic relationships of different rock units within the field site. The top unit is the Loch Raven Schist. Under the Loch Raven Schist is the Cockeysville Marble. Underneath the Cockeysville Marble is the Setters Formation. Under the Setters Formation is the Baltimore Gneiss.
Closer image of outcrop showing the parallel layers that are being weathered to expose the planar undersides. A couple of drill holes are present in the face of the outcrop. A sub vertical dike is exposed cutting through the layers in the outcrop. Most of the outcrop is weathering gray with some reddish weathering surrounding the dike. Green moss and white lichen cover some of the outcrop.
A finger points to a close up of the rock. It has white minerals and dark minerals interspersed somewhat homogeneously with no obvious layering. The white grains are sand-sized and the dark grains are smaller.
Another close of of the same rock texture but showing a slight indication of a foliation within the grains due to their common orientation and possible stretching which in this photo is from top left to bottom right.
Another close up with a finger pointing to grains with a metallic sheen and a micaceous habit.
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