The Spanish Treasure Fleets 
  After the bureaucratic organization of Spanish empire in the New World, the colonists could hardly eat, drink, buy, sell, be born, move about, or die without paying taxes to the Church or to the State. Only Spaniards born in Spain could hold public office. Indians, mestizos (offspring of Spaniards and Indian), and even criollos (all white descendants of Spaiards) had little or no political or social standing. Nor could any of the colonists acquire, other than by smuggling, any of the wares of European civilization except those sent from Spain in Spanish ships to designated colonial ports. In short, Spain imposed a monopoly.
  Beginning in 1561, and lasting until 1748 with few annual exceptions, the Spanish government sent two merchant convoys each year to the New World. They brought consumer goods and took home the wealth from the mines. These convoys, known as treasure fleets, had to be escorted by Spanish warships or were themselves warships, as protection against raiders of all types, not only pirates but privateers of Holland, France, and especially England. Often there was little distinction between a pirate ship and one operating clandestinely or semi-officially on behalf of another European government, for it was the aim particularly of the English to break the Spanish monopoly and gain their own footholds in the New World.
  The Spanish fleets assembled in Cadiz and Seville and made their way across the Atlantic, one fleet to Veracruz in Mexico and the other to Portobello in Panama, to unload European goods for the colonists. Then the empty ships loaded their holds with New World gold, silver, gem stones, and in later years silks and other exotica shipped from the Orient via the Spanish-controlled Philippines to the Pacific coasts of Mexico and Panama, thence by land to the storehouses in Veracruz and Portabello. For the voyage back to Spain the divided fleet reassembled in Havana before riding the Gulf Stream up the east coast of Florida and across the Atlantic. The whole operation was supposedly timed for departure from Cuba before the advent of the hurricane season in July.
  Also in these convoys were the treasures from South America, all previously brought to Caribbean assembly points from Callao (the port of Lima, storehouse for the western South America) and Catagena (storehouse for the New Granada or Colombia). These southern territories were also supplied by the same Granada or Colombia). these southern territories were also supplied by the same fleets from Spain, via Panama, although in later years directly so to Cartagena, whose gigantic forts and city walls can still be seen today.
  British attacks were frequent, both before and after 1588, the year of the defeat of Spain's famous Invincible Armada off the coast of the British Isles and the beginning of the end of Spanish primacy on the seas. Even before 1588 the ships of Francis Drake plundered the Pacific as well as the Caribbean ports of the Spanish colonies. Equally well known are the exploits of Walter Raleigh, or in the next century those Henry Morgan and many other freebooters, Dutch and French too. To know who ultimately prevailed, all it takes is a glance at any current map of the Caribbean areas and a nation of the geographical distribution of languages other than Spanish: Dutch in Curacao; and French in Haiti and Martinique, not to mention farther down the line the three different languages of the Guyanas, or to the south of them the whole huge nation of Portuguese-speaking Brazil.
  Brazil is a special case, neither whose history nor whose coinage have we attempted to cover. for there are no Brazilian cobs. For 60 years, beginning in 1580 when Philip II of Spain was also King of Portugal, Spain controlled the Portuguese colony of Brazil, which consisted mainly of coastal towns less ambitiously organized than those of Spanish America. Earlier and by means to spheres of interest which in South America took the form of a demarcation line, north to south, that designated Brazil to be Portuguese territory. Unlike the Spanish part of the New World, Brazil developed very slowly, at first because it was a penal colony, not unlike the later British one in Australia, and an almost entirely coastal one without any large-scale exploitation of mineral resources. So forbidding were the Amazon and the vast jungles that only in twentieth century has Brazil begun to exploit and populate this vast interior.
  Spain, at the apogee of her power in the sixteenth century, was to remain dominate only so long as the gold and silver continued to flow in from the New World. It was a false prosperity like that of the accidental heir to a fortune who, instead of investing wisely his newfound capital, indulges himself in reckless spending until the wealth is finally gone. The precious metals did not remain in Spain as national capital for the formation of a permanent base of industry and prosperity. Instead the treasure flowed Madrid for military ventures around Europe or for short-term enterprise within Spain.
  Take the case of Philip II who, like his predecessor and successors on the Spanish throne, always got his quinto or royal fifth of all treasure transported from America. National economic policy was always secondary to the extermination of religious heretics. What for example, were the workers to do after they had built his extravagant Escorial palace? Or how was Spain, much of it rocky and infertile anyhow, to be reforested after the same monarch ordered so much timber cut down for the building of his Invincible Armada that turned out not to be invincible after all? In modern economic terms, Spain lacked the resources and tax base to support its military power by any means other than gold and silver from America. Scarcely any treasure fleet arrived with wealth that was not already pledged for the reduction of arrears on ever-increasing debts to the banking houses of Europe. Spain was destined to diminish in power along with the inevitable diminution of plunder of the New World.
  During the almost three centuries that Spain managed to hold together her interests in the New World, a fair amount of the colonies' mineral wealth came to rest on the bottom of the oceans rather than in European treasuries. Some of the gold and silver was lost to buccaneers, much of it to storms at sea. This is not surprising when you consider the size of the Spanish treasure ships, from bow to stem only about 150 feet 9the three "ships" of Christopher Columbus less than 75 feet each), toys in comparison with the mammoth ships of today, themselves not immune to the devastating force of a hurricane.
  The science of sea-salvage has developed rapidly in recent decades. New diving techniques and sophisticated equipment for exploration in very deep water now entice investors around the world to form companies for the attempted salvage of known wrecks. Records of locations of shipwrecks are being searched as never before. Governments are devising new laws to define jurisdictions over marine territory and percentages of successful salvage to be retained by the government.
  In October of 1981 divers of a Yorkshire, England, salvage company brought up about four hundred Russian gold bars worth $81,000,000 (at the time) from the British cruiser Edinburgh, scuttled in May, 1942, after torpedoes from German submarines and destroyers had rendered her helpless north of Murmansk. Still more bars were recovered from this ship in 1986, the proceeds parceled on a percentage basis among the salvors, Great Britain, and the Soviet Union, as the gold was originally Russian payment to the U.S. for war materials.
  Even the Titanic has been located and explored, but most worldwide salvage operations have been concentradted on the treasure-laden wrecks of centuries past. Whatever the nationality of the older sunken ship, it was usually carrying world-trade coins, including cobs. Here are some of the wrecks and fleets whose cargoes have found their way into either the promotional or numismatic marketplace in recent years; only ships that have yielded cobs are listed:

          1554, "1554 fleet" (Spanish), several of the ships sunk off Padre Island, Texas. Mostly Mexican coinage of Carlos-Juana, some of which still appears on beaches of Padre Island.

          1585, Santiago (Portuguese), sunk between Mozambique and Madagascar. Many silver cobs of both Spain and Spanish America, some rare.

          1622, Atocha and Santa Margarita (both Spanish), sunk in a hurricane southwest of Key West, Florida. The much-publicized salvage operations of Mel Fisher and his Treasure Salvors company produced vast amounts of Spanish American silver cobs, most of which had suffered greatly from the long immersion and then harsh cleaning process. Highly promoted. The salvage included a representative group of the earliest Colombian silver cobs, some dispersed privately, others offered at the Christie's New York auction of June, 1988. See account of the Margarita salvage in February 1982 National Geographics, preceded by an early account (before the main treasure was found) of the Atocha salvage in the June 1976 National Geographic.

          Circa 1628, "Lucayan Beach treasure," Grand Bahama Island. The name of this ship or ships is unknown. Most have been Mexican of the assayer D period.

          1641, Concepcion (Spanish), sunk off the northern coast of what is now the Dominican Republic. About 60,000 mostly Mexican silver cobs. Highly promoted. A number of rare Colombian cobs, including more from the Cartagena mint than had been found on any other shipwreck, was offered at auction by Henry Christensen, Inc., in 1982. The site is still being worked from time to time.

          1656, Maravillas (Spanish), sunk in the Bahamas. Mostly Mexican and Potosi silver cobs, modestly promoted. This area, Little Bahama Bank, not far from Florida, is still being worked occasionally, as the main treasure may not yet have been found. Other locations in the Bahamas have yielded cobs too, apparently the names of the ships are unknown.

          1659(?), San Francisco y San Antonio (?), sunk close to shore off Jupiter Inlet, east coast of Florida. Salvage of what appear to be numerous Spanish American silver cobs has begun, but it is still too early to be sure that the wreck site represents a major discovery.

          1682, Joanna (British), sunk off Cape Agulhas, tip of South Africa. Quantities of Spanish American silver cobs, most of them 4 and 8 reales of Charles II.

          1707, Association (British), sunk near the Isles of Scilly, south west coast of England. Quantities of Spanish American cobs, especially those of Lima and Potosi.

          1708, San Jose (Spanish), sunk by the British off Cartagena, Colombia. The wreck was located by commercial salvors in 1981 at a depth of over 750 feet, very deep and very costly for salvage, although the main problem has been indecision on the part of the Colombian government in the award of a contract. This is potentially the richest single-ship recovery of them all, as revealed by the manifest of the ship. This vessel was the largest of a twelve-ship convoy, the only significant fleet to sail to the New World during the War of Spanish Succession (a civil war in Spain, part of a generalwar in Europe), when the seas were dangerous for normal treasure-fleet operations, and also Spanish ships were needed elsewhere. The San Jose is reprted to have been transporting 30 million gold and silver cobs, 116 chests of emeralds, and the personal wealth of the Viceroy of Peru. Even if the figures are exaggerated, or not all the treasures can be located, it is a ship whose salvage is eagerly awaited.

          1711, Feversham (British), sunk off Nova Scotia, Canada. The entire corpus of material, mainly Spanish American silver cobs and Massachusetts Bay Colony shillings, not a large salvage by comparison with the cargoes of Spanish treasure ships, was auctioned  by Christie's in New York, 1989.

          1715, "1715 Fleet" or "Plate Fleet" (Spanish), eleven ships sunk in a hurricane off the east coast of Florida and scattered many miles apart in an area from south of Melbourne to south of Fort Pierce. Vast quantities of Spanish American gold and silver cobs, more gold than found in any other shipwrecks before or since. Promoted originally by the Real Eight Company, offered at auction by Henry Christensen (1964), Parke-Bernet Galleries (1967), the Schulman Coin and Mint (1972 and 1974), and Bowers and Ruddy Galleries (1977), and recorded pictorially (excellent photos of coins and the entire early operation) in January 1965 National Geographic. These salvage operations were not only among the first, from the early 1960s, but have been of the greatest numismatic importance of them all, and are ongoing even today, for only six of the ships have been found. For these reasons, an account of the destruction and salvage of the 1715 fleet will follow.

References

For additional information see:  "The Practical Book Of Cobs," by Daniel Sedwick and Frank Sedwick, Library of Congress Catalog Card Number 94-67562