One of the world’s most storied coins is the Spanish real, which was Spain’s denomination at the height of the nation’s dominance as a world power in the 16th century. Silver eight-real coins were worth one Spanish dollar, and were the source of the phrase “pieces of eight,” which has been associated with pirates and ill-gotten treasure since 1883, when Robert Louis Stevenson put the phrase in the mouth of Long John Silver’s talkative parrot.

In fact, reales were so widespread in the New World that they were one of the most common forms of currency in the U.S colonies, and were traded as legal tender throughout the new nation in the early years of the United States. Reales from the mid-19th century ranged in value from 1/20th of a real (the media decima, minted in copper) to 100 reales (the gold doblon, commonly called the doubloon).

In 1848, Spain’s monetary system underwent the first of three decimal conversions. At first the real was pegged at 10 decimas; in 1854, the exchange was set at 100 centimos. In 1864, a silver version of the escudo was also determined to be equal to 100 centimos, which was a bit of a come down for that historic coin—in the 1500s, one gold escudo was worth 16 reales. To add insult to injury, the escudo was replaced altogether in 1869 by the peseta.