The working notes from the Trautman Art Glass site state:
This glass comes transparent, but kiln-strikes into a super-dark antique ruby red. Can be reduced. Work cool or heat your bead back to transparency at the end of your flame working time, to prevent it from getting "muddy."
(I haven't tried reducing it, yet. I also find no trace of muddiness - which is gratifying.)
Trust me - I didn't work this stuff cool. On the other hand - I didn't have to heat it back to clear, either - it just looked clear the entire time I worked it. But I didn't particularly super heat it either. I just made a gather and wound off a bead.
The first pic - the bead on the left is self-coloured (only Black Cherry - by the way - self-coloured is a term from my doggy life - meaning all one solid colour - in case that's been confusing you.) The middle bead had a clear core (I was worried about these getting to be too dark!) and the right hand bead is encased with clear. They are all pretty consistent for colour. The larger one is darker because it has more coloured glass.
Additional working notes for Black Cherry from TAG continue to explain that the colour deepens with the length of time spent in the kiln, and with higher temps too. They explain that in order to get the colour you want, do a test bead and put it in the kiln and garage it, and check it every 10 mins until you get the colour you want, and then run your annealing schedule. As the bead continues to strike duringing annealing - you may then want to adjust the garaging time - in order to have the bead come out exactly as you want it.
This, as they say, "gives the artist a great deal of control as to the exact colour" and they suggest making your Black Cherry beads at the end of your working session - and then adjusting your annealing schedule to get optimum colour.
The first set of beads I made, were, in fact - made at the end of my working session. I have my kiln continue to hold the temp at 950 for an hour after the last bead, and the entire ramp down takes about 8 hours after that, the way I have it programmed. As you can see - not so dark.
So, the next session - I made the beads earlier - and they got an additional 1.5 hours garaging at about 950. (I think my kiln actually runs a little hot - 945 is where I have it set - I think it's closer to 960 actually.)
You can see here - from the second session, Black Cherry encased in clear. This is a much nicer, richer colour. I would suggest making these at the beginning of your bead-making session - and that gives them lots of time to develop colour - but your milage may vary. It occurs to me that I might run the first beads through another annealing and see if I develop a nicer colour.
TAG also notes that this glass varies from batch to batch - so remember that when you re-purchase it - your striking time may change.
It's a really nice shade of red. Not being able to see the colour while working it is a little frustrating - and I'm not much for planning ahead in order to adjust my schedule to get the exact, specific shade.
But is it a really nice red. I'm on the fence on this one. Really nice colour versus waaaay too much thinking/planning about it.