According Edward Kann, who was a member of the Advisory Mint Committee during this time, the silver versions of this issue dated Year 22 were struck between June 1933 and May 1934 with original dies prepared at the Philadelphia Mint. A slightly modified design from the Year 21 issues, the birds and rising sun were removed in favor of a more simplistic reverse. The off-metal strikes, in brass, copper or other compositions, represent special presentation pieces of the adopted design.
This fantastic piece may be appearing for the first time since it was lot 913 in Superior's Irving Goodman sale (where is sold for $396), described as "Essay Dollar. CD 22nd Year (1933). cf. K-623x. Struck in brass, unlisted. 23.33 grams. Milled edge. Standard design." That amazing auction had three other Year 22 patterns, none of which have reappeared, so far as we know.
Ex: Superior (Beverly Hills 6/1991) The Irving Goodman sale lot # 913 (tag included).
Estimate: $20000 - $40000