Dichromic glass

I just love Jewellery! This is a necklace made of dichromic glass, I honestly can't remember the process, but I love the results! I bought it at Wicken Fen at the weekend, in the National Trust gift shop, I loved the colours, they reminded me of a butterfly wing or a dragon fly.
I hope it's warmer where you are, it's cold, damp and miserable here :-( I am hoping for better days ahead xxx