Gold Doubloons And Pieces Of Eight

What You Need to Know About Collecting These Coins

Gold doubloons and pieces of eight are Spanish colonial coins from the 16th through early 19th centuries. The doubloon was a gold coin worth two escudos, while the piece of eight was a silver coin officially called the real de a ocho. Both types show up constantly in treasure diving and in auction catalogs. They are real coins with real history, but the market around them is messy. The basics are straightforward. Doubloons were minted in denominations of 4, 8, and 16 escudos. The 8-escudo piece is what most people mean when they say doubloon. It weighs roughly 27 grams and is composed of about .917 fine gold, depending on the mint period. Pieces of eight were silver coins weighing around 27 to 28 grams at .903 fine silver during the main colonial period. Both coin types feature the Spanish coat of arms on the obverse and the pillars of Hercules with the motto "PLUS ULTRA" on the reverse. The key is to look at the mint marks, date placement, and lettering style to narrow down which decade or kingdom produced it. I once bought a lot labeled as a gold doubloon from a small dealer who knew less than I did about colonial Spanish numismatics. The coin looked right at first glance. Gold color, correct weight, correct diameter. But when I checked the edge lettering and the positioning of the crown on the obverse under magnification, the strike was clearly off. The letters were too deep and the metal flow around the stars was wrong. It was a modern replica cast from a genuine coin mold. I sent it back without argument. The dealer did not respond to my emails, which is typical for that kind of setup. Always insist on return privileges when buying unverified colonial coins from someone you have not worked with before.

Grading and Market Reality

These coins do not grade well by modern standards. The soft silver and gold alloys, combined with centuries of burial in seawater or sand, mean most surviving examples show heavy wear or environmental damage. A piece that looks clean to a casual buyer is often a coin that has been chemically cleaned, which destroys collector value. Do not be tempted by a shiny specimen at a reasonable price. Cleaning these coins is the single fastest way to drop their value by half or more. NGC and PCGS do slab these coins, and a certified holder adds liquidity to your purchase. But even a slabbed coin requires verification. I have seen duplicate slabs with different serial numbers floating around online auction sites. When a coin arrives, go to the grading company's website and look up the serial number yourself. If the certification picture does not match the coin in your hand, you have a problem. This takes about three minutes and has saved me from spending thousands on a fake slab on two separate occasions.

Where These Coins Actually Come From

Most gold doubloons and silver pieces of eight in private hands originated from shipwrecks in the Caribbean, along the Florida coast, or in the Philippines trade route. Spain moved enormous quantities of precious metal through those waters between 1550 and 1820. Many coins survived because they were sealed in barrels, wrapped in cloth, or buried in ship storage compartments. The saltwater exposure changed the surface patina in ways that are distinctive to trained eyes, but also easy to replicate with artificial aging techniques. The East India Trade Route coins, minted in Mexico City or Lima and shipped to Manila, tend to have different die varieties and wear patterns compared to coins lost in Atlantic wrecks. Knowing which route a coin likely traveled helps you evaluate its authenticity and rarity. A Mexico City doubloon from 1732 carries different catalog references than a Lima piece from the same year, even if they look nearly identical to an untrained observer.

Common Pitfalls for New Collectors

The biggest trap is assuming all old Spanish coins are valuable. Most pieces of eight in circulation are worn down to basic state examples with limited premium over melt or face value. A heavily worn 1772 Mexico City piece of eight might sell for two to three hundred dollars, while a better preserved example from the same era can go for several thousand. The difference is often just a few visible details on the crown or the pillars. Another issue is counterfeit dates. Engravers have altered base dates on worn coins to make them look rarer. A 1755 dated coin might have been carefully filled and re-engraved to read 1772, which is a much scarcer date in some varieties. Use a loupe and check the letter edges for tool marks. Re-engraved dates will show irregular cuts and uneven depths under magnification.

Storage and Preservation

Keep these coins in a stable environment. Changes in humidity cause silver to tarnish faster, and gold coins with copper content can develop surface oxidation if stored improperly. Use inert materials like polyethylene or polypropylene holders. Avoid vinyl holders, which contain plasticizers that migrate into the coin surface over time and create a permanent dull film that cannot be removed without damaging the coin. If you find coins with salt crust still attached, do not attempt to remove it yourself unless you know exactly what you are doing. Salt deposits can protect underlying detail. Aggressive cleaning exposes fresh metal to air and accelerates degradation. Place the coin in a sealed container with a humidity indicator and let it sit in a stable indoor environment for several months. The crust often stabilizes on its own. There are good sources for learning more about these coins beyond dealer catalogs. The Royal Mint of Spain publishes historical mint reports, and several university libraries have digitized colonial records that list mintage figures for individual years. Cross-referencing those records with your coin's mint mark and date can tell you whether you are holding something genuinely rare or just a common example in decent condition.