My medium is watercolour. A tutorial showed ‘Gamblin Cold Wax’ being used to rub over the dry painting to preserve it if it is not being framed. My painting was only being mounted on board with a map board frame and placed in a cellophane envelope for sale. I put some of the wax onto a clean white cloth then gently rubbed it over the painting and continued to buff the wax to ensure it had a very thin even coverage. It worked very well. The Watercolour paint was not affected at all. The protective layer of wax also brought the colours out beautifully. I highly recommend this product.