Hi Redwinch,
Yes, I know where this mine is: it's Llanrwst in North Wales. We were there only about 2 weeks ago!!! This is a shot of the extant remains of the engine house for a horizontal engine.
[photo]Personal-Album-2602-Image-30966[/photo]
The chapel is still in the bottom of the valley but the conifers have grown up around the site a lot since your shot of the early 1980s obscuring it somewhat. The engine house is just above an activity centre.
A good picture of the site appears on the front cover of John Bennett and Robert Vernon's book
Mines of Gwydyr Forest Part I, Llanrwst and its Neighbours (1989)
The extant remains of the engine house and chimney appear to have been consolidated between your shot of the site and that on the book cover.
Den heb davaz a gollaz i dir