Mexico, 1980 AD., Mexico city mint, Medallic Silver Bullion Coinage, 1 troy ounce of silver, KM M 49 b.5.

Mexico, Mexico city mint, Medallic Silver Bullion Coinage, 1980 AD.,
1 troy ounce of silver (41,5 mm / 33,65 g), 0.9250 silver, 33,63 g theor. mint weight, mintage 6.104.000 , coin alignment ↑↓ (180°), reeded edge,
Obv.: CASA DE MONEDA DE MEXICO / 1980 , around coin press.
Rev.: UNA ONZA TROY DE PLATA PURA / LEY / .925 / PESO / 33.625 / GRAMOS / Mo , around and between scales, left scale pan points to the U of UNA (Type 5).
KM M 49 b.5 .