Just to show you I do use straight glaze colors sometimes without mixing them.
And here's my experiment.
I did some test tiles to come up with a pale turquoise, and this is the result. Bermuda Green mason stain from Highwater mixed about 2 oz dry into a wet batch (about 1/2 gallon) of Satin White. It's much lighter than our celadon. And I haven't tried it on stoneware yet, just on the white clay. There are a few speckles of darker color, but it doesn't pit, is evenly spread, and doesn't break very much on the grooves.
More tests to follow. I like the glacier or ice berg quality this gives.