This is apparently the only coin known from Zacatecas in 1866. On November 29, 1866 Zacatecas was recaptured by the Republicans from imperial forces, who had held the city for nearly three years. Presumably the mint was not prepared to resume the coinage of Republican types, and no coins at all of 1866 have ever been reported for Zacatecas. Unique and unpublished.