Not to be confused with Phoenix Precious Metals, Phoenix Refining Corporation was actually a New York refiner. Their iconic hallmark is a rocket going through the O. Most ingots found today are type 2, as pictured below — these show up in 1 oz commercial art bars all the way up to 5, 10, and 25 oz+ pours. The type 1 is exceptionally rare: only the rocket hallmark on the obverse with no name stamped, and just a handful have been discovered in the 5 and 10 oz class. Long out of production, they trade only on the secondary market now.
I came across a 100oz Phoenix bar in 2017 wen buying silver for staking and became obsessed with it ! Great history behind this bars and really hard to find!