mason stains I ordered in California, I finally know. I found them in an unopened box on the bottom shelf of my kiln cart. They were at the back hidden by posts and glaze mixing supplies. I also found two thermocouples. Doesn't say much for my organization skills. Ha. Nice to know I have them for my next studio. I mix mason stains in clay slip and brush designs on green clay. Then I bisque fire the pieces. Next they get a clear glaze and are fired again. For more details about the process I use to make the slip and mix the stains go to this link.