Cracked bead, why?

[noora]

As you can see, this bead has cracked. Any ideas why? It's Effetre white, fuchsia frit (if I remember correctly), Effetre 006 clear. I made it several weeks ago and it was fine when it got out of the kiln. It's been in my uncleaned beads jar and I noticed the crack today when I was cleaning it. Can you tell from how the crack goes if it's a problem with the annealing or incompatibility (too much frit perhaps)?

[Kalorlo]

Thermal cracks in small beads are normally parallel to the mandrel - that looks more like incompatibility, so maybe it was a bit too much frit in some areas.

[noora]

Thank you 

If I remember correctly I was actually starting to think I might be adding a bit too much frit when I was making the bead. Seems like I was right...

[Kaz]

Try to stick to around 5% frit of the whole bead. Is it 94 frit? if it's a lower COE than that, it may be completely incompatible e.g. I would not try to use COE 90 (bullseye) with standard 104?
Kazx

[noora]

Kaz, in fact I think it's the fuchsia from your reactive variety pack (the ones you made for FO)

I have another bead with perhaps a little less of the same frit (made at the same time) and that one is still intact.