gold dichroic on black
silver dichroic on black
clear glass with dichroic squares
these are millefiori fused together. If you fuse them with other glass you may have in your stash,
and dont know the Coe numbers, they may not be compatible eg. Coe 90 with Coe 96,
they may well crack your fused piece.
Sometimes this doesn't happen immediately, but may well do at some stage later.