This is the regular 1922 Sandblasted Proof high relief dollar. Although long collected as one of the prime rarities in the Peace dollar series, it is actually a pattern produced when J2018 was rejected. These were struck with a new reverse die which has the length of the rays through the N in One, and also the the ones under the P and R in Pluribus being longer on the 1922 reverse as shown below. About 20 are believed to have been struck based on the envelope accompanying the Baker example sold in I&L Goldberg's June 2014 sale. Photo courtesy of PCGS.