Those bars are marked. It does look similar to the unmarked ones. What size was it do you remember. I'll ask Jack if he still has that one. The mystery deepens
I just called Jack to ask him about the bar in your photo. He said he marked that bar Silver King for his class. Needless to say he is interested in the bars in my photos. The Silver King had bars taken and hidden in the early years. That would be so cool if the bars were Silver King silver
The drill holes look to be (not exact) but very similar to each other (configuration wise) on both sgtfda's and oasis's bars.
I was referring to the bars in my photo. Jack did say those molds were used early on and after some thefts they started casting in 200 pound bars. I wonder if that same type mold was used by other mines also during that time period