Fuseworks so called dichroic glass not quite compatible?

[noora]

In fact it seems like the brick shelf didn't heat up fast enough, because the pieces are unevenly fused/firepolished. The edges on the bottom of the glass pieces are still a bit sharp. Since there doesn't seem to be any stress in the glass, I assume the shelf reached at least 520 but not quite the top temperature. I guess the ramp up to the top was too fast for the shelf to warm up, and I only soaked for 10 minutes at the top.

I always cool down through the annealing range at a slow ramp, but I got a feeling that the shelf slowed down the ramp even more. At least the last bit (below 370) where I let the kiln cool down on its own took much longer than usual.