Potosi, Bolivia, 1-sol monetary medal, 1851, Constitution.
Burnett-37; Fonrobert-9558. 3.42 grams.
Obverse with open-book Constitution with CONS / TITU / CION on left page and BOLI / VIANA on right page inside legend JURADA EN 28 DE OCTUBRE DE 1851
Reverse with Cerro de Potosi with llama to left and wheat to right under radiant sun inside legend REPUBLICA BOLIVIANA; reeded edge. 

This example shows favorably to a similar example in an NGC MS63 holder. Nice high grade with luster in the peripheries.