Paris: Plaster Thereof

The town of Paris is a beautiful place to collect.  The whole town seems to have the right mixture of straight, hard stone lines and soft curving hills, but I had a special interest beyond that in my desire to find the gypsum I needed for making the icon’s gesso.  I had always assumed that the town had been dubbed Paris in honour of the capital of France, but the name actually comes in honour of what the gypsum-rocks collected in abundance here was used to create: Plaster of Paris.  Going all the way back to 1822, Paris was a centre for gypsum mining.  After reading that little fact in a Harrowsmith magazine a while back, there was nowhere else in Ontario that I was going to go to collect my rocks.

Plaster of Paris is made from cooked gypsum and it is good for making traditional gesso.  Gypsum comes in a huge variety of forms but all of it is composed of calcium sulfate.

We made three stops in Paris.  The first was along the Cambridge/Paris Rail Trail in a location that Reiner had collected from with his father many years ago.  We left the Rail Trail after a short hike and descended down to the riverbank.  Back when Reiner first came here he said that the site was a clean cliff where the minerals could be seen.  Since then clay and mud has begun to slide down from the top and cover everything.  Our only chance in finding some gypsum in these conditions would be to locate some that had been washed down from above.


As we walked along we found a lot of very interesting rocks, and then we found a chunk of gypsum (you can see it in my hand in the photo above).  I was surprised at how soft the rock was, and how white.  Once you’ve seen it, you won’t mistake it for anything else.  We looked along the bank for other gypsum rocks, but ended up returning to where we had found the original piece.  After a little digging we began to find more and more of it; unexpectedly, we had found a vein!

Over the next hour we dug up two bags-full of wonderful gypsum. This represents more than enough plaster of paris for the whole project.  For our first stop, this was a wind-fall, but in discoveries that followed I was to be surprised at the many forms that gypsum takes.

While in Paris we traveled to another location that held the promise of gypsum.  Parking in the downtown, we followed a trail along the south side of the river keeping our eyes peeled for more white rocks.

I was looking for a white, powdery rock such as we had collected on the other side of the river, but when Reiner said he had found some he handed me something quite different.  This rock was hard and it contained crystals.  These crystals weren’t a contaminant, as I supposed, but are the crystalized form of gypsum called Selenite.  So the rock I was looking at is still completely pure gypsum!

We didn’t find nearly as much rock at this location, but we did find something special.  Among the gypsum-rocks we did collect we found one that came complete with it’s own pedestal in the form of some limestone it was still attached to.  This is a beautiful example and something you can look for at the exhibition in September.

We did head out to a third location in Paris.  Maggie had found where the original mines of Paris were located and more out of historical interest than any other we decided to walk along the bank and see if we could locate any remains.  In the end we did find an adit entrance, but not of a major mining operation.

This really wasn’t a major disappointment.  The walk along the river was wonderful and richly diverse and the visit to Paris had yielded the desired gypsum in spades.  This was a really great trip and with a trunk load of gypsum I headed back to my studio.


For this collecting trip I was joined by Reiner and Maggie. Collecting rocks with Reiner is always a treat because of his knowledge, experience and the sixth sense he has for finding rocks.  Maggie was also a great help.  In preparation for the trip she conducted all the research we would need to find the locations where it was likely find the desired gypsum.  My thanks to both.

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