KM-unlisted.  Struck in white metal. Multiple mint errors are found on this undocumented pattern piece including being struck without a collar, having the "TP XE" engraved on the obverse die backwards, and both sides exhibiting strong die clashing.  As a result of being struck without a collar to restrain the expansion during the strike, the rims are unusually wide and the legends near the rims exhibit spreading characteristic of a broad-strike.  The fields are proof-like and bright.  A unique mint error pattern.

Curiously, the NGC insert lists this as being a 10% off-center error rather than as being broad-struck.