“We’re right on Scotch Hill, which was the site of the first slate quarry in western Vermont — on the border of Castleton and Fair Haven,” Vermont Historical Society executive director Steve Perkins said. “We’re right at the northern end of what’s called the Slate Valley or the Slate Belt, where one finds in the Taconic Mountain Range this great outgrowth of the rock, slate, that we know. I think to learn more about this, what we need to do is go to the Slate Valley Museum in Granville, New York — right across the border — and talk to Sarah Kijowski, who is the executive director.”

“Slate, contrary to what most people believe, is actually a metamorphic rock; it’s not a sedimentary rock,” Kijowski said. “It’s formed from a sedimentary rock, shale, which originally settled in the Valley. Over millions of years in plate tectonics — mountain-building activities — everything was sort of squished. The tremendous heat and pressure basically baked the stone into a metamorphic rock and that’s what we know as slate today.”

Mike Hoey asked, “We can see now a very visible sign of how the process starts, but how is it excavated?”

“Earliest on was (by using) this machine right here,” Kijowski answered. “They would blast holes into the ground, and people would be working down in the bottom of these pits extracting the stone, and they would hoist them out. That really was the way of the industry until World War II ended and we had a lot of surplus machinery that became available. People came into the Slate Valley and started purchasing that equipment — dump trucks, forklifts, things like that — and that’s when they were building roads into the bottom of the quarries and they could begin to truck the slate out of the quarry. The market’s not really big enough to use all of the waste, so when you drive around the Valley, you’ll still see massive piles of waste, or they call them rubbish piles.

“Originally, shanties were located — multiples of them — around the quarries, so as they work in the quarries to get the big chunks of slate out of the ground, they work it gradually into smaller and smaller chunks,” Kijowski continued. “Eventually, it makes its way here as a block. This is where it’s split by hand, using a hammer and chisel, where the edges are trimmed using the trimming machine over there. This machine here is where holes would be punched into it for application onto a roof. So, as time went on, the technology improved. We use the heavier equipment I mentioned earlier, post-World War II — trucks, things like that — they’d truck it all to a centralized location, which is a mill. So that’s where we are today; most places have a mill.

“In addition to slate roofing — which has been the mainstay, as I mentioned — and flooring and things like that, slate has also been used artistically in things like carving,” Kijowski said. “We have a nice example of a contemporary bench here, as well as lots of novelty items, whether historic or modern, things like piggy banks, little decorative clocks, pool tables, things like that. They’ve tried to use it as many places at they can. Sometimes it seems a little hidden, but it has lots of different uses.”

“Including chalkboards,” Hoey said. “You know the old expression ‘wiping the slate clean’ — it comes from somewhere.”