White Paint (Chalk White), 1857

The Druggist's General Receipt Book (1857) has some general observations on the different materials used in rouge and white paints. For the latter, it mentions the vinegar-treated talc I've already experimented with, as well as the widely-condemned white lead and liable-to-turn-grey-while-worn bismuth "pearl powder". An intriguing note I've not seen elsewhere is that French chalk can be used in place of talc, with or without the addition of zinc oxide*. Starch and magnesia (MgO) are also named as "face whites", the later primarily in America.

The wood mortar is good for breaking up clumps.

I started by setting 20 mL of powdered chalk and 40 mL white vinegar to sit for a week; without specific amounts given, I used the same proportions as in the talc. This vinegar step is supposed to make the talc or chalk more white, but I haven't noticed any color changes. As expected, the slightly basic chalk reacted with the acidic vinegar, producing gas bubbles. Otherwise, the process went just like the before: stirring every few days, then pouring off the vinegar, rinsing the chalk with water until the vinegar scent is gone, then allowing the chalk to dry. The chalk does settle more easily than the talc did, making it easier to decant off the vinegar/water. I took part of the chalk and mixed it with an equal volume of zinc oxide*.

 

Barely visible to the eye, and not visible in the photograph.

I tried both the chalk and zinc-chalk powders on my skin, but observed no differences between the two. There really was no change in color, and even looking closely I saw only the slightest hint of white. Compared to the talc white, neither of these chalk whites are very noticable.  

*Which is used in modern sunscreens. Though the Victorian distaste for wearing paint during the day (/at all) probably means this was not used an early attempt at sun protection. The toxicity data I could find suggests that ZnO is safe for topical use, but this powdered form might present an inhalation risk. Since this is an experiment (and I won't be using it regularly), I decided to make part of the batch with the ZnO to see how it behaved.