Joanne,
You have gotten some great suggestion on using Aion over a dark transparent base. Here is what I wrote up for the Third Silver Exchange that may be of interest to you:
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• wind a football (American football! lol!) shape of Medium (or Dark) Amethyst
• completely encase Amethyst core with Aion 2
• let bead cool until the glow is gone, start warm up your clear (I use Diamond Clear
• reduce Aion 2 in a reduction flame (my yellow candles are about 2" and my bead is another inch or so above the tip of the yellow candles)
• let cool and reduce again
• go back to a neutral flame, keeping the bead warm by flashing it at the tip of the flame quickly in and out without "erasing" the reduction, melt Clear
• encase completely in Clear by keeping the bead beneath the flame as not to erase the reduction
• shape bead and press
• flame polish out chill marks
• pop in kiln (don't look at your bead too long or it will crack like mine down the mandrel line! lol!)
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Steph Bonniwell and I did a tutorial on Striking Silver Glass using Luna 2, the link is on my siggy line. Unfortunately it's a lot more difficult to strike silver glass using a HH for it is usually not hot enough to get the glass white hot/droopy.
Also, do you have Luna which is milky translucent in rod form or Luna 2 which is creamy translucent? Luna 2 is a lot easier to strike than the original Luna.
Hope this helps!