Our Treasure of the Month for June is this triple dated 1686 silver eight reales coin from the Spanish colonial mint at Potosi. It is rare indeed to find two dates on a Potosi eight reales coin as the dates were typically off the planchet when the coin was struck. But here we have an example of three dates on a single coin.
Two of the dates can be found on the obverse of the coin. A large “86” is seen below the center and the full date of “1686” is located at the bottom of the coin in the 7:00 o’clock position. On the reverse, an “86” is seen just below the bottom of the cross.
Weighing in at 27.03 grams, this coin was produced during the 35 year reign of Charles II (1665- 1700). At that time Potosi was part of the Viceroyalty of Peru (now Bolivia). Handmade silver coins (known as cobs) form the mint at Potosi are known for large planchet cracks which was due to the silver alloys used to make the coin which resulted in the coins being brittle. Also, a further explanation can be found in the fact that the silver was not properly annealed which can result in the silver becoming brittle if it is hammered without annealing. Whatever the case, most (not all) Potosi coins do not have the same overall smoothness found in silver coins from the mints at Mexico City and Lima.
Our featured coin is a recent find recovered after Hurricane Nicole which brought such great devastation to Florida in November of 2022. Below are pictures of the coin (left side) shortly after it was recovered. The bluish-green encrustation or patina on the coin is the result of the interaction of the silver with the environment around it. Compare these images to the coin (right side) after it was conserved.
If you pay close attention to the obverse of the coin you will see the initials “VR” which stand for Pedro de Villar the mint assayer who worked at the Potosi mint from 1679 to 1697. He is the most common assayer encountered on Potosi coins found on 1715 Fleet wreck sites.
For more about Potosi coins see our Treasure of the Month for January 2013, June 2013, April 2014 and October 2014.