Using encaustic medium (damar resin & beeswax) to make medieval seals!

This year I'll be teaching Hands-On Medieval History in my kids' homeschool co-op. I wanted them to learn about the Magna Carta and other medieval official documents and then make their own. Of course, that means making seal stamps (matrixes) and using sealing wax.

Fascinatingly enough, the medieval sealing wax was not the same as the sealing wax used today, or even during the 1700s. It was really just wax and resin, and was warmed with the hand--rather than melted over a candle.

I went down a long rabbit hole trying to figure out how to make this cool stuff. The first thing I read was this cool article by Imprint (from the University of Lincoln and the Aberystwyth University), where they make their own seal wax and color it with viridian (toxic teal made with copper) and vermillion (toxic red full of mercury). They struggled a lot to get the consistency right, and there were nasty fumes from heating the resin. That did not sound like something I wanted to mess with, but it still sounded super cool!

Imprint's historically accurate medieval sealing wax!

After diving down the sealing wax rabbit hole, I found this webpage detailing making wax tablets and wax seals. In the post, they say,

Artists' encaustic medium would serve well as sealing wax, but I believe from my experiments that three parts beeswax mixed with two parts encaustic medium would serve better for a writing tablet.

And I thought, "Hey, I could just buy this stuff and see if it works!" It's the same stuff used to make cool mummy paintings, and people still make encaustic paintings today.  So I ordered a bag of encaustic medium off of amazon and started experimenting!

Encaustic medium in nice, meltable pellets

This stuff thankfully comes in hand little pellets that warm up in your hand relatively easily. They try to roll out of your hand initially, so I'll probably portion out pre-formed little "wafers" for my students so I don't have pellets of wax and resin stuck in the carpet!

My daughter was able to warm up the wax by herself, and had a lot of fun mixing in my natural, non-toxic earth pigments into the wax to make her own custom purple sealing wax. I made a teal and red wax using the pigments, too. I did find that the resin was slightly irritating to my hands, but that was after warming and blending 4 different seal sets. They felt fine for the first three. I'll have the kids wash their hands afterward.

To add the color, what I did was warm up the wax until it was really soft and then "dip" it into the pigment. I feared that this would be messy, but it really wasn't. It stuck nicely to the wax, and any pigment on my hands was picked up by the wax. The only color that was messy was chalk powder (which I used to make the lighter purple).

I found this wax does stick nicely to paper, and will probably stick nicely to string like the old medieval documents. I'll try imprinting it tomorrow with one of my seals (I can't right now, because my kids are sleeping and I'd probably wake them trying to get to my seal stamps.)

But, i wanted to make sure to document this for future me, and for others who want to easily (and more affordably) make authentic medieval seals. You can even buy colored encaustic medium if you don't want to color it yourself. But, I think the coloring part is fun, and then you aren't working with toxic pigments (unless you really want the seal to be authentic!)