I ran a tack fuse of some uroboros glass on Spec and BE. Temp got to 1425 with a short hold. Is that enough to determine compatability. The Uroboros glass was not listed as fusible but it wad the MOST GORGEOUS glass I have seen in awhile and would love to use it in a fuse. So far the results show compatability with both but the glass has not cooled compl;etely. Thanks. Ann
With only a tack fuse Marty is right you may just get away with an incompatibility. Try sticking it in the freezer and see if will handle the temperature extreme. This works at full fuse too when you are looking for residual stress in opaque glass.