1928 Maryland Geological Survey Map Showing the Etchison Chrome Mine Location. Published March 18, 2010 at 352 × 463 in 1928 Maryland Geological Survey Map Showing the Etchison Chrome Mine Location. 1928 Maryland Geological Survey Map Showing the Etchison Chrome Mine Location. Shortlink for this post: https://wp.me/a1bnGQ-2M