Interesting article, I would challenge the location and type of mine, the silver part I don't doubt, I've never heard of any coal mines in that part of Idaho, (Wrong geological rock location) and Oneida County is in Idaho, not Utah.
I have researched several of these myself and i live around this location, I was shocked to find out just how much silver and gold came out of this area while growing up, including copper, but Idaho has to ship in all of its coal for its power station and I've never heard of any coal producing mine around this area.
The Mormon influence in this area was not for coal, this came from South central and Central Utah, I do a lot on the emigration research and have never heard of coal in this region.
Good Luck! Stay Gold!
Opie
I grew up in that area, and knew of several small coal deposits in the hills above Franklin and Richmond. I never heard of any above the Cove area but it seems like there was a story about a small coal deposit above Smithfield.
I know of several small silver mines in the same areas and there was a story circulating in the late 70's about a large, deep silver deposit up Smithfield canyon that was too deep to be profitable. I didn't get out much North of Preston so I don't remember any stories from that area.