The larin was a Persian coin that acted as international currency in the Indian Ocean trading area in the sixteenth through eighteenth centuries. For reasons unknown, the city of Lar in Iran gave its name to the larin, but the coin seems never to have been minted in that city. The larin was a silver coin.

As coins go the larin was a bit unusual, even for a period as early as the sixteenth century. Rather than a coin struck from a circular blank of metal, the larin was made of a strip of silver wire, bent in two, and stamped with circular or rectangular dies. The Safavid Shah Tahmasp, ruler of Hormuz, now southern Iran, struck the first larins during the mid-sixteenth century. India and Ceylon also minted larins, as did Arabia under the Ottomans, but the larins struck by the Safavids traded at a premium, owing to the purity of their silver metal.

In the sixteenth and seventeenth centuries larins were overvalued in terms of silver content, and silver flowed into Persia from European trade with the Levant. The law required Persian merchants receiving foreign coins to bring all these coins to the mint to be restruck as larins. The merchants had to pay the mint charge but the overvaluation of the larin offset these costs.

During the seventeenth century the Spanish real, forebear to the U.S. dollar, began to displace the larin in Indian Ocean and Far Eastern trade. Persian merchants smuggled in Spanish reales and Persian caravans and sea-going vessels laden with reals left Persia for trade with India. Early in the eighteenth century the Iranian and Indian currency was unified and the new currency was called the rupee, but by then Spanish reals dominated world trade.