"Pounce is a fine powder that was sprinkled over wet ink to hasten drying prior to the invention of blotting paper. The powder was prepared from substances such as finely ground salt, sand, or powdered soft minerals such as talc or soapstone. A mixture of sandarac gum, and pumice or cuttlebone serves as pounce and can also be used for sizing paper and vellum."
Pounce was made from ground cuttlefish bone, sandarac and other items. Note sandarac currently sells for $55 a pound on eBay and is therefore out of my price range for this project. The pounce I made can be used for both paper sizing and as a blotter. For use with sizing I mixed with ground rosin instead of sandarac. Both are varieties of tree sap. One of my kids dropped their cake of rosin while moving their violins around. It cracked and was therefore replaced by the violin store. As the rosin had no more use to my kids it became available for my SCA use.
Here is a picture of the cracked up rosin cake.
I used the rosin as a cheap and available substitute for sandarac. The rest of the materials used were ground up cuttlefish bone, ground pumice and ground salt. I mixed 5 parts cuttlefish bone, 4 parts pumice 2 parts rosin and one part salt. I ground up each material individually and them combined them all and reground them mixture. I then sifted the final mixture to extract any large portions of pumice or bone flakes which were not fully ground up.
Here are some pictures of the cuttlefish bone before and after It was ground up.
Here are some pics of the pumice stone I used before and after it was ground up.
I didn't take any photos of the finished product, but it doesn't look much different than the ground up ingredients. I have a project on my list to someday make a period looking pounce pot, but for now I keep the pounce in a glass jar. I plan on putting it into a small salt shaker for use, until I finish the pounce pot.