Decades after Christopher Columbus’s first voyage to the New World from 1492 to 1493, the Spanish conquerors discovered vast quantities of gold, silver, and copper. This discovery increased the influence of Spain in the world economy. Not only were large quantities of these three metals important to Spain from its colonies, the nation became the center of an empire that traded with the rest of the world, importing and exporting goods among other nations.
Before the mid-16th century, colonial mints that produced gold and silver coins had not yet been built in Mexico or Peru. Hernando Cortés, the first conqueror of Spain in Mexico, sent to Spain the few precious metals that could be looted and smelted from Aztec and Tarascan jewels, idols and other artifacts. These items were cast into raw bars of gold, silver, and copper. But there was a problem: the bars never made it to Spain.
In the summer of 1992, a treasure rescue boat off the western coast of Grand Bahama Island detected an incredibly large amount of buried metal in the ocean. When the family who worked for Marex donned their scuba gear to investigate, they discovered several silver and gold bars, but that discovery was only the tip of the iceberg. After contacting the Marex headquarters, more than two hundred raw bars were brought to the surface from the same site.
After investigating the gold and silver ingots, poured with some copper, the archaeologists discovered that they came from a Spanish ship that sank in 1528, as a result of a hurricane or that the ship ran aground in shallow water. Most of the bars could be identified from the marks that had been stamped after they had been cast as thoroughly, but as quickly as possible, using raw molds, some of which were mere depressions in the sand.
These bars called “tumbaga” were identified by four details engraved on each one:
1. The letters BV with “~” above the B and “o” above the V, possibly signifying Bernardino Vásquez, one of Cortés’s fellow conquerors, who supervised the mixing and molding of each bar.
2. The purity of each bar was marked in Roman numerals as a percentage of 2400 for 100% pure; 1200 for 50%, 600 for 25%, and so on.
3. Serial numbers, beginning with the letter R followed by Roman numerals.
4. Tax stamp, part of a circular seal whose legend (assembled) reads CAROLVS QVINTVS IMPERATOR of Carlos V, King of Spain and Holy Roman Emperor. The seal probably indicates the “Fifth of the King”: 20 percent of the treasure goes to the King.
The discovery of this collection of bars is of great historical significance to the vast and exciting stories of shipwrecked “Spanish treasures” such as the chests filled with gold doubloons from the early Spanish colonial empire. In addition, it is the oldest treasure that was discovered in the Atlantic Ocean since the Spanish coastal empire between 1492 and 1820. The treasure was originally artifacts that were looted and smelted from the Aztecs and other pagan Native American tribes; the conquerors were primarily subjugating the native population and did not require regular excavation of mines before 1528.
The word “tumbaga” comes from a historical document of a Spanish governor in the Philippine islands of the early 18th century who used the term “Metal de tumbaga” to refer to an alloy of gold and copper used among the natives. The current term also includes a silver-copper alloy, which comprised most of the bars. (See attached link for “Tumbaga Saga”).