Coin, silver base. Diameter 24 mm. Weight 13.25 grams. Condition good. Denomination: silver base tetradrachm. Obverse description: Head of Ptolemy I, facing right, diademed, aegis around neck, border of dots. Reverse description: [inscription] Eagle on thunderbolt, border of dots. Mint date: Alexandria, year 22, reign of Ptolemy XI, Alexander I.