'Jet black' is a bit of an exaggeration. But it is black - perhaps with hint of purple. Certainly not toffee coloured like now and odd that it changed colour within a few hours.
I haven't tried it yet, I replenish in a Nova so it's going to be mixed with the older Blix that's fine. The concentrates are old - the dev I bought at the same time died recently and I am about to make a new order at ag for blix.