1556, Mexico, Charles & Joanna. Nice Pillar Silver 2 Reales Cob Coin. R! Assayer: O Mint year: 1516-1656 Mint Place: Mexico (oM) Reference: Calico 120. R! Denomination: Pillar 2 Reales Cob Ruler: Charles I (as King of Spain – Charles V as Holy Roman Emperor) together with Joanna of Spain. Diameter: 26mm Material: Silver Weight: 6.3gm Obverse: Crowned pillars of Hercules above w ...