Yep, I have always loved the "sparkliness" of unobtainium in boro (for the unititiated its a sparkly metallic glass) but the love affair is officially over..... *you can picture here me stamping off in a huff!
I used the knobbly end of my vacstack pull to make a marble last night.... it was big and beautiful and a little bit swirly. It was one of those occasions where I couldn't wait to have a peek into the kiln this morning and because I was using my minor burner (read baby torch for boro working) it took me about an hour and a half to finish off I had visions of absolute beauty and was keen to get some job satisfaction from my glass baby........ NOPE, definitely not happening.
I know there are quite a few boro colours that do not like to be encased and will now add Unobtainium to my list (particularly in big lumps). My lovely mib had gone all "crackylicious" on me, but only where the stripes of unobtainium were, here's a pic so others can learn from my mistakes ;-)
As you can see my baby had a good and a bad photographic side. I had even popped in a little clownfish murrini at the end like a signature because this marble was the biggest I had made so far - nearly 2 inches in fact.
Lifes a learning curve I suppose - clear encased thick unobtainium.... EPIC FAIL!
**Note: if you shut your eyes and hold it in your hand..... still lovely!