Decimal issues of the Guanajuato mint

Copper

One centavo 

Diameter 25 mm. 

Silver

Five centavos

Diameter 15 mm. 1.353 g. 0.9027 silver 

Ten centavos 

Diameter 17 mm. 2.707 g. 0.9027 silver 

Twenty-five centavos

Diameter 25 mm. 6.768 g. 0.9027 silver 

Fifty centavos

Diameter 30 mm.13.536 g. 0.9027 silver 

One peso

Diameter 37 mm. 27.073 g. 0.9027 silver 

Diameter 39 mm. 27.073 g. 0.9027 silver 

Gold

One peso

Diameter 15 mm.1.692 g. 0.8750 gold 

2½ pesos 

Diameter 18 mm. 4.230 g. 0.8750 gold 

KM-411.3 $2½ 1888 Go over Mo (Briggs & Bustos auction VIII, April 2024, lot 382)

Last date struck at the Guanajuato mint in this rare denomination, the key piece with a mintage of only 110 pieces reported. Elusive as are all the 1888 issues, a very interesting fact is that all of these were struck with a reverse with a re-engraved Go/Mo mint mark, none of them show any trace of an over-assayer. 

Five pesos 

Diameter 22 mm. 8.460 g. 0.8750 gold 

Ten pesos 

Diameter 27 mm. 16.920 g. 0.8750 gold 

Twenty pesos

Diameter 34 mm. 33.840 g. 0.8750 gold