Ultramarine Blue: Purify Resin

When my children and I collected the sap from the pine trees, we also ended up with extra bits of bark, bugs and leaves.  I didn’t think that this would help in my little project, so I set about purifying the sap.

The simplest way I could find to purify the sap was simply to light it on fire.  I did this over a simple, homemade strainer and as the impurities burned out, the resin flowed to the container below.  This was easy and fast, but it produced a black glob of resin.  This still might have every bit as well worked, but I thought I would be more comfortable if I could make resin that wasn’t so charred in appearance.

Sorted pine resin.

Here’s what I did: I tied a good amount of the resin into a loose weave cloth and tied it up.  Then, I put this into boiling water and let it boil for the morning (the bag slowly extruded the sap over that time).  By noon I had a nice thick layer of resin floating on the top of the water which I collected with a spoon.  The results are a nice brown, sticky mass that I am confident will help in my creation of ultramarine blue.

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