Oracle-Black has smooth working characteristics, reads "darker" than some existing black glasses, does not spread excessively, and can be worked very hot without boiling. It is made in USA without Antimony, Arsenic, Cadmium, Chromium, Lead, Nickel, or Selenium.  Rods are blue but strike to black during the annealing cycle.  Stays neutral with striking colors but reacts to luster colors.  

For maximum opacity, particularly in thin applications, briefly cool the bead then lightly flame strike (30 seconds) before annealing for 2 hours or more at 950F.