By: shelley-jaye
Image: Photo credit: Robin Rohrback, Mid-Atlantic Geo-Image Collection (M.A.G.I.C.) on GigaPan. CC BY Attribution 3.0. Definition credit: Wikipedia licensed under CC BY: 3.O Attribution. ⧉
License: Creative Commons Attribution ⧉

Uploaded: 17 Jan 2020
Last Updated: 17 Jan 2020

618 megapixels
32,260 x 19,164 pixels
107.5 in X 63.9 in at 300dpi

Amphibolite from Great Falls, MD. Amphibolite similar to the amphibolite exposed on the Billy Goat Trail. Amphibolite is a metamorphic rock very rich in the mineral hornblende (an amphibole), which shows up black in this image. The white mineral in the rock is plagioclase feldspar. This is a very mafic metamorphic rock, with large crystals. Amphibolite occurs as large, folded, tabular masses in the area of the Billy Goat Trail.