Black azoth. Tarry, used for porters/cumbers.
Silver azoth. Mythical. Said to raise the dead.
Gold azoth. Suppresses aging.
White azoth. Dangerous - siphons life on contact and turns red.
Red azoth. A gel that encourages healing.
Desperate citizens can make a penny applying white azoth to themselves to turn it into valuable red. But most of the red azoth on the market has less ethical origins.