Anyone with a manufacturing background can attest to the need for prototypes. Before producing a large quantity of anything, it’s always important to produce a test sample. Coins are no different. In the United States Mint’s 200+ year history, it has consistently produced prototype or “pattern” coins to test various designs, metals, formats and techniques. The result is a fascinating branch of American numismatics.

Some pattern coins look exactly like their regular issue counterparts but were struck in a different metal. For example, let’s say the US Mint wanted to test out the dies for a $20 gold piece but didn’t want to waste an ounce of gold on the test run. Instead, the Mint might strike a few coins in copper or aluminum first to make sure the dies functioned properly. These “off metal” patterns were made with some regularity in the 1870s through 1880s.

Other pattern coins were struck to test a new design altogether. They were used to demonstrate what an artist’s or engraver’s proposed motif would look like in the flesh. Unfortunately many exquisite designs never made it past the pattern stage because they were difficult to produce or considered too edgy. Sometimes pride got in the way too—often tenured US Mint engravers blocked attempts to replace their tried and true designs.

Perhaps the most intriguing category of pattern coins are the experimental formats and denominations. Examples include one dollar gold pieces with Mint-made holes in the center, $4 gold pieces, giant $50 Half Unions, and even plastic coins made during World War II. These pieces are some of the wildest and most unusual coins ever released by the United States Mint; their novelty factor makes them extremely valuable and desirable.

Pattern coins vary tremendously in value, from just a couple thousand dollars to eight figures. The more mundane issues (especially common off-metal pieces or coins with minor design variations) trade for $5000 and less, even if just 10-30 pieces are known. Patterns with gorgeous and unusual designs can sell for dramatically more, depending on rarity and condition. The most exotic pieces—especially those with fascinating backstories—can sell for millions. For instance, an 1880 pattern nickel might only sell for $5000—but an equally rare 1880 pattern $4 gold piece is worth $500k-$1.5m. The former is considered more pedestrian, while the latter has an unusual denomination and historical background.

In conclusion, pattern coins are an enthralling category of United States coins. They are an important part of American numismatic history, as they demonstrate the changes and modifications applied to America’s coinage over the decades. Most pieces are extremely rare, unusual, fascinating—or a combination of the above. Prudent collectors can buy scarce and intriguing pattern coins for relatively little money.