yeah, that's right, colorado had a northern coal field-lignite lays in a flat bed varying from 2-20 ft in thickness and ranging in depth from outcrops to 400+feet in a belt extending from marshall to frederick, colorado, just east of where i live. all mining ceased as of 1975 and unfortunately not much evidence of the industry remains on the surface.
its doubtful that any mine openings remain since the horizontal beds were accessed with shafts and the workings are most likely filled with water. the state of colorado had a pretty aggressive reclamation program that closed them up and now most of the region is experiencing sub-urbanization at an unbelieveable rate. there are a few mine fires still burning, subsidence is an issue in certain areas and developments and shopping centers are named after the mines they stand over-a few of reminders of colorado's coal mining history.....
any thoughts on the age, etc, of my cap?
http://www.ironminers.com/mineforum/vie ... php?t=1207
also, any experts out there on colorado coal mining?