{Tips Julia found for us on the web on using "Evil Devitrifying Purple":

Some tips on taming the evil beast that resides inside of your purple.

The first assumption is that purple is an attempt to make an opaque gold ruby. Inside your rod is gold ruby dying to get out and shunning the substance trying to make it opaque.

This combination is not stable. Whatever it is that makes purple opaque, and gold ruby do NOT like each other and they try to separate.

The trick is to bring that gold ruby to the surface without unleashing the the devitrification process.

Temperature is everything...very hot is good ....very cool is good but in between is fraught with the demon devit.

You can make dots of purple on a base bead....just heat your stringer in the flame and place it on the base bead and move on to your next. When you get done with all of them then heat the whole bead back to glowing quickly. It is the in between temperatures that make the color a bit unstable and it tries to separate...

What purple can't stand is being warm and then rewarmed.

So reheat to glowing...the whole bead or ...let the bead cool... What I hope you can see in this picture is that the fushcia color is in spots...you can see a pale band in between the two more colorful patches. Look at the rod of glass...you see that same effect in a rod that has been melted and cooled...rapidly!

So, after you have made your purple bead, let it cool. Then bring the bead up under the flame and just let the flame kiss the surface of the top of the bead. You will see an orange glow.

This is a heat reaction on the surface and you are freeing the gold ruby from its scum. This is a brief kiss in the flame, move on.
Once you have brought this color to the surface it is much more stable. Treat the whole bead this way with just little spots of heat to bring a glow just to the surface and you will see the gold ruby rise. Repeat the process around your bead...letting it cool. You will know right away if you have not cooled enough because you will see some devit forming. You might see some graininess near the bead hole, that can be tolerated.

After you have heat treated all of the surface of the bead...take it back to the full flame for a few turns and then into the kiln.

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