A small coin was recovered outside the hull under a piece of lead abaft the sternpost on the starboard side. Dull gray in color, and highly encrusted with corrosion products, the coin (00,544) is in very poor and fragmentary condition. When placed in a storage solution of sodium sesquicarbonate, it tinted the solution green, suggesting that the coin was made of copper. Rather than attempting to clean the piece by mechanical or electrolytic means, a decision was made to treat it in an air-tight container with a solution of alkaline dithionite for two weeks in an attempt to reduce the corrosion products back to the parent metal. However, due the the apparent lack of core metal, the treatment was only successful in loosening the outer corrosion products from the sulfided core. Once the concretion was removed, the coin and its encrustation still retained sufficient detail to be drawn and photographed for tentative numismatic identification. Both the core and outer concretion were consolidated in acryloid B-72 folowing dehydration by a series of alcohol baths.
Fig. 70. Once the concretion was removed from this encrusted Spanish coin, details emerged which helped identify and date this copper coin, a blanca, minted between 1471 and 1474 during the reign of Henry IV. Corrosion product (left), Obverse side of coin (right).
Photographs of the coin and encrustation were sent to Dr. John Kleeberg, Associate Curator of Modern Coins at the American Numismatic Society, who showed them to his colleague, Dr. Alan Stahl. They identified the coin as a billon blanca, minted between 1471 and 1474, possibly at the Cuenca mint during the reign of Henry IV (1454-1474) of Castille and León (John Kleeberg to R. Smith, 6 July, 1995) The term billon (vellón) refers to coinage made from an alloy of silver heavily debased with copper. Blanca was the lowest denomination of coins minted during this medieval monarch’s reign.
Features discernible at the upper right quadrant on the obverse side of the fragmentary coin are the edge of the castle (symbol of Castille) within a lozenge (diamond) encircled by a beaded ring. At one o’clock are visible the letters H E, which are part of the legend HENRICUS DEI GRACIA. On the reverse side of the coin, visible also on its encrustation in a mirror image, is the rampant lion (of León) within a lozenge surrounded by a beaded ring. At the top corner of the lozenge is the Cross of Jerusalem, and at 11 o’clock the letters R E, which are part of the legend XPS VINCIT XPS REG. On both sides of the coin various annuletes (punch marks) can be discerned at the sides of the lozenges, a characteristic of Henry IV blancas.
A similar blanca is described in two standard Spanish numismatic catalogs as a dinero (Castan and Cayon 1980:202; Cayon and Castan 1991:279). However, Dr. Stahl believes this designation is incorrect; his study of medieval mint decrees indicates that blancas of this type replaced earlier coins in 1471, and continued to be minted until 1474, when Henry was succeeded by his half-sister Isabella, who married Ferdinand (A. Stahl, pers. comm., 1995). During their reign, no other copper-based coins were issued until the coinage reform of 1497.
Fig. 71. Type 28 blanca minted in Cuenca, Spain 1471-1474. (From Cayon and Castan 1991, not to scale).
Fifty-nine blancas of this type were unearthed during excavations at La Isabela in the Domincan Republic, the first European settlement in the New World, which was founded by Christopher Columbus in 1494 (Stahl 1992; Deagan 1992). A single blanca of Henry IV also was found at the Long Bay site on San Salvador Island in the Bahamas, which is argued to have been the first American landfall of Columbus in 1492. Analysis by atomic absorption and emmission spectography of the San Salvador coin determined that it contained 3.97% silver and 95.7% copper (Brill 1987).
According to Dr. Stahl, Henry IV blancas were a principal medium of exchange that was used in the Americas upon the arrival of Spaniards. Circulation of these coins probably decreased in Europe after the minting reforms of Ferdinand and Isabella in 1497, and ended in the Americas after 1535, when the Mexico City mint began a large coinage output (John Kleeberg to R. Smith, 6 July, 1995). Discovery of this late medieval example of “small change” at the stern of the Emanuel Point Ship prompts questions as to the longevity of circulation of these coins by Europeans in the New World. By the 1550s, this would have been an old coin of little negotiable value; perhaps its provenience aboard the sailing ship was that of a keepsake or pocket-piece belonging to a passenger or crew member. Or, the coin came aboard very early in the ship’s career, was lost by its owner, and continued with the ship to its last port of call. Another possibility is that the coin may have been present among older ballast stones that were loaded aboard the ship at an established port, where dumps of recycled stones were available to vessels in need of additional ballast.