The dull, sort of chalky look is what happened to some of my boolits after the second coat (prior to baking) when they were left on the drying screen overnight out of doors.
There were two stacked racks left out, both second coats from the same batch of coating. The first coating and baking went fine. The second coat went on fine, with all the casts having a nice glossy surface, but the next day there were shiny coated boolits on the top rack (those on the right in the image) but dull ones were on the lower rack (those on the left), mainly those on top of the pile (the ones underneath those were shiny), and mainly on the upper exposed part of the boolits.
The coating was my standard mix of 20 grams in 120 ml of acetone, about 5 ml for a weighed five pounds of casts. Each five pound batch was spread out for the initial drying, and then scraped together in a pile left in the screen. No contact between the top and bottom screens, and the casts were dumped just barely wet. No rain overnight.
After baking the second coat the dull casts were back to shiny, and all have passed the wipe and smash tests. I haven't shot any yet.
So, I'm not sure what caused the change in appearance. My guess is condensation, though why it affected only the lower rack i really don't know. I'm pretty sure it wasn't liquid coating dripping down from the top rack (I don't think I have ever dumped really wet).
It seems, with the normal appearance post baking and the passes on testing, that there was no harm done, but I still would like to know what happened. Any thoughts?