Portrait of José de San Martín to the right.

José Francisco de San Martín y Matorras (1778–1850), known simply as José de San Martín or El Libertador of Argentina, Chile and Peru, was a Spanish-Argentine general and the prime leader of the southern and central parts of South America's successful struggle for independence from the Spanish Empire who served as the Protector of Peru.

San Martín is regarded as a national hero of Argentina and Peru, and one of the Liberators of Spanish South America. The Order of the Liberator General San Martín (Orden del Libertador General San Martín), created in his honor, is the highest decoration conferred by the Argentine government.

Engraver: Mario Baiardi

Value, legend in circle around, date below.

There are variants reside in the different stretch of the edge for 1951:
• thick edge (15 s/cm - stretch)
• thin edge (21 s/cm - stretch)
• irregular edge