This is a technique called "Eden", where special frits with hints of lead are arranged and fired at very high temps, causing them to "blossom". Some colors bloom better than others.
I plan on Cold-working these into night lights and possibly Keychains or fan pulls. In a couple days, I plan to try out my new Porter Cable, Table-Top wet saw

~ along with my glass saw and grinders. Then I will give them a polish-fire and attach hardware.
Christmas gifts ~ provided I'm happy with them

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