Reales issues of the Guanajuato mint (8 reales)

 
KM-377.8 8r 1870 Go YF (Stack’s Bowers auction, 7 August 2012, lot 40688)

Diameter 39 mm. 27.070 g, 0.90277 silver

 
KM-377.8 8r 1830 Go MJ (Ponterio Chicago ANA auction, 13 August 2011, lot 20547)
Full "J", die style of 1830-43.

KM-377.8 8r 1831 Go MJ (Stack’s Bowers auction, 31 October 2023, lot 70433)
Three periods after date / Full "J" variety.

 
KM-377.8 8r 1831 Go MJ
three stars after date

KM-377.8 8r 1897/2 Go RS (Stack’s Bowers auction, 31 October 2023, lot 70558)

Counterfeits

Counterfeit KM-377.8 8r 1828 Go JM (Briggs & Bustos Counterfeit issues II, 10 August 2025, lot 68)

Contemporary counterfeit, struck on a copper or bronze planchet. Noteworthy for the assayer initials rendered as “JM” instead of “MJ”. Other differences can be seen in the design of the cap and eagle, which at first glance appears thinner with less detail in the feathers; the edge is also slightly crude. Matches the same dies as the low-silver specimen illustrated by John Leonard Riddell (No. 283).

Counterfeit KM-377.8 8r 1831 Go MJ (Stack’s Bowers auction, 30 October 2024, lot 73253)

Has a single dot after the date and narrow or straight "J". Porosity of surfaces and incorrect style of lettering, and insufficient weight are three factors pointing to its status as a contemporary counterfeit.

Counterfeit KM-377.8 8r 1831 Go MJ (Briggs & Bustos Counterfeit issues II, 10 August 2025, lot 69)

Contemporary counterfeit, struck on a very low-grade silver planchet. Features a reverse design imitating the variety with a straight “J”. Overall very similar in proportion and engraving style, although the eagle’s relief lacks the depth of a genuine specimen. Same dies as the example illustrated by John Leonard Riddell (No. 297).

Counterfeit KM-377.8 8r 1834 Go PJ (Briggs & Bustos Counterfeit issues II, 10 August 2025, lot 70)

Contemporary counterfeit struck on a very low-fineness flan, distinguishable by its peculiar engraving. On the reverse, the cap is slightly wider, its outline rounded, and it has fewer folds; the rays show little variation in length, and the number 4 in the date fades at the bottom. On the opposite side, the eagle is recognizable by its thin neck. Matches the same dies as No. 314 reported by Leonard Riddell.

Counterfeit KM-377.8 8r 1840 G PJ (Briggs & Bustos Counterfeit issues II, 10 August 2025, lot 71)

Contemporary counterfeit struck on a very low-grade silver planchet. Notable for displaying the mintmark “G” instead of “Go” on the obverse, as well as a raised “LIBERTAD” legend on the Phrygian cap — opposite to what is observed on a genuine coin.

Counterfeit KM-377.8 8r 1840 G J (Briggs & Bustos Counterfeit issues II, 10 August 2025, lot 72)

Contemporary counterfeit, struck on a planchet of an alloy known as alpaca. Reverse with atypical legend by virtue of the mint mark G instead of "Go" and assayer with a single initial "J". The design is a little less detailed, however, the engraving denotes skill on the part of the forger.

counterfeit KM-377.8 8r 1844 G J (Briggs & Bustos Counterfeit issues II, 10 August 2025, lot 73)

Contemporary counterfeit, struck on a planchet of mixed composition. Easily identifiable by the unusually pointed cap and the absence of the “o” in the mintmark G(o).

counterfeit KM-377.8 8r 1844 C PJ (Briggs & Bustos Counterfeit issues II, 10 August 2025, lot 74)

Contemporary counterfeit, struck on a flan of mixed alloy. Very crude design and rough manufacture. Reverse with an inconsistent legend combining the C mintmark and the PJ assayer initials; interestingly, the “D” in “10D” is replaced by a reversed “C”, and the “G” in “20G” by a regular-position “C”. It seems the forger attempted to imitate a piece from Guanajuato and, lacking a punch with the letter G, simply used the closest available character— in this case, the letter C.