I picked out opal yellow glass the other day - huge rods with lots of pink - they also had a batch with hardly any pink at all in the bin.
I can't find my picture where I made my bead just plain - somehow it had a light blue in it to.
The blue it could of been another color picked up on the rod. I am still looking.
I tryed the OP with that new Violet today - it's still in the kiln.