Yes, an example of odd narrow gauge clay pit operations in the U.S. would be of interest to some on this forum.
The first image shows the 18" gauge GWEN hauling several tons of clay "tubs" on a line near Burton-on-Trent in England. This line was barely 3/4 of a mile from pit to refractory plant, yet used two 5-ton steam locos for 59 years. The JACK (1989) and the GWEN (1920) were retired in 1957 (named for the children of a mine executive, perhaps the owner).
The GWEN has been restored to operational, builder's photo condition as shown in the second photo, and resides in California of all places. The JACK also survives in operational condition at the Leeds Industrial Museum in Leeds, Midlands, England.
Bob of AZ