I visited the Cononish mine a few years ago (as a geologist) just as the current operation was getting going. Unfortunately we were not permitted to take photos for company confidentiality reasons. If memory serves however the majority of wagons were small round bottomed tippers or flats based on the same chassis. We saw no loco but there was what looked like a charging point for a battery electric near the mine entrance.
My lasting impression of that visit was that it is a very wet mine! Most of the upper levels were drained naturally but there was a substantial throughput of water and everything underground was well rusted and festooned in algal or mineral growth. You can therefore go to town on your weathering!
If you search Tyndrum Gold Mine Railway on the Web a small number of photos of the wagons will pop up.
Best regards from Sweden, George!
