Editor's note: The following is the first of a two-part Coin World series about the blending of history and technology in a new collector coin from Portugal, prepared by Jeff Starck for the November 2014 monthly edition of Coin World.

Mints take great pains when striking coins to avoid making errors, but at first glance, the Portuguese State Mint’s newest silver €2.5 coin, with a disc of gold hanging off the coin, might look like a misstrike.

The coin is not an error; rather, a portion was struck off-center on purpose.

Creating the coin’s distinctive appearance is the latest salvo in the battle to develop new technology for modern commemorative coins. While the technology for making these coins is not quite as earthshaking as, say, a drone strike, the efforts of the Portuguese State Mint (Imprensa Nacional-Casa da Moeda) are making noise in the marketplace.

Collectors have seen map-shaped coins, coins with jewels and precious metals embedded, coins struck with space-age metals, and even coins with centers made from a different metal or element. But collectors have never seen anything quite like this, as the relatively small Portuguese State Mint appears to be joining the vanguard of commemorative coin technology, competing against larger national mints like the Royal Canadian Mint and Britain’s Royal Mint, which have publicly poured millions into research and development.

A collector’s first thought of a ringed-bimetallic coin might be the ringed-bimetallic coins circulating in Canada ($2) or the eurozone (€1 and €2), but this new coin from Portugal gives that concept a twist.

Portugal’s mint calls it the world’s first “eccentric” coin, based on the technical meaning of eccentric, referring to something not placed centrally or not having its axis placed centrally. While the point could be debated that many coins, with their gems or technological gizmos embedded, could qualify, the new commemorative coin certainly is in a class by itself, with a gold disc intentionally jutting off a larger silver canvas, resulting in a noncircular coin.

A key distinction might be that the overall product is one coin, not a design created from two or more individually denominated coins, a recently popular motif.

Why was the coin made?

The Proof 2014 coin celebrates the 100th anniversary of the Republic of Portugal’s first commemorative coin.

On the obverse of the silver area is a replica of the obverse of the coin issued in 1914, which was the first to bear the face value of 1 escudo. A replica of the last commemorative escudo coin (struck in 2001 in gold) is found in the gold area on the obverse, resulting in a single face containing two coin images.

The reverse bears an image of the old Casa da Moeda where the 1914 coin was minted, along with a detailed view of the entrance of the modern day Casa da Moeda where the 2001 coin was minted; on the right-hand side is its face value, displayed as 2,5 EURO. The gold part visible on the reverse bears the legend 1914 – 2014.

Oct. 5 is celebrated as Revolution Day in Portugal, to mark the beginning of the First Portuguese Republic, which was established in 1910 after King Manuel II of the Braganza dynasty was overthrown.

In 1911, the escudo debuted, replacing the real, at the rate of 1 escudo to 1,000 réis. Between 1912 and 1916, silver 10-, 20- and 50-centavo and 1-escudo coins were issued. In 1914, a 1910-dated silver escudo coin was issued, with an allegorical figure representing the Republic and the anniversary date 5 OUITUBRO DE 1910 (Oct. 5, 1910) on the obverse. The crest of the new republic along with the coin’s denomination appears on the reverse.

The 2014 coin was designed by Nuno Caetano.

António Salgueiro Verdasca, head of the commemorative coin unit at the Portuguese State Mint, told Coin World, “There are lots of bimetallic coins shapes around the world with all kinds of inserts, but in this case the smaller disk goes beyond the edge of the bigger one and this is part of the novelty of this coin.”

The coin was sold out before its Oct. 1 release, with the entire 2,500-coin mintage purchased during distributor and domestic sales that began sometime in mid- to late September.

The coin had an official issue price of €172.20 (about $217.49 in U.S. funds), which is not much more than the retail price for one gold coin and one silver coin matching the specifications of the components in this “eccentric” coin.

Collectors who obtain one might just find it priceless, thanks to the unique, secret minting process developed for the coin.