Latin Monetary Union: coins, silver and gold

The Latin Monetary Union was a currency agreement signed in Paris on 23 December 1865 and dissolved on 1 January 1927. It fixed a bimetallic ratio of 15.5 to 1 between gold and silver and let member states strike coins to shared weights and fineness. For a collector, the practical result is that a French 5 francs piece, an Italian 5 lire piece and a Belgian 5 francs piece from the right years are the same coin in different clothes.

That agreement is the reason a beginner can pick up a silver coin struck in Turin, Brussels or Paris and read the same specifications off a catalogue page. The French-language review L'Union Latine covers the convention, the coins and the market, including the 1865 monetary convention and its twelve-date chronology.

1. What was the Latin Monetary Union?

It was a treaty, not a central bank. France, Belgium, Italy and Switzerland signed in 1865, and Greece joined in 1868. The four founding states agreed to strike gold and silver coins to identical standards so that each state's coins would circulate in the others' territory.

The core specifications were simple. Silver coins of full value were struck at 900 thousandths fineness, with the 5 francs piece weighing 25 grams. Gold coins were struck at 900 thousandths as well, with the 20 francs piece weighing 6.45161 grams. The bimetallic ratio of 15.5 to 1 meant that 15.5 grams of silver were declared equal in value to one gram of gold.

Each state kept its own currency name, its own designs and its own mint letters. What was shared was the weight, the fineness and the legal-tender status across borders. That is why the series is studied as one group rather than as four or five national series.

The union did not survive the First World War. Member states suspended convertibility, issued paper, and debased their silver. The formal dissolution came on 1 January 1927.

2. Why does a Civil War reader care about a French coin treaty?

The dates overlap, and the overlap is not a coincidence of the calendar.

The American Civil War ran from 1861 to 1865. The Latin Monetary Union was signed in December 1865, in the same year that the war ended. Both events sit inside a decade when governments on both sides of the Atlantic were rethinking what a coin was worth and who guaranteed it.

In the United States, the war years brought greenbacks, the suspension of specie payment, and a premium on gold that fluctuated with every campaign report. In Europe, the same years brought a push to standardise coinage across borders so that trade would not have to weigh and assay every piece. The problems were different in scale and in politics, but the underlying question was the same: what makes a piece of metal a coin?

For a reader who has spent time tracing a regiment through state records, the coin record offers a different kind of trace. A soldier's pay, a sutler's prices, a widow's pension payment, all of these moved through money that was itself changing. The numismatic record is a second ledger of the same years.

3. How do you identify a Latin Monetary Union coin?

Start with four things: the country, the date, the weight and the fineness.

The country is usually on the obverse, in the ruler's title or the state's name. The date is usually below the bust or in the exergue. The weight and fineness are not on the coin; they are in the reference works, and they are what make the coin part of the union rather than a national issue that merely looks similar.

Mint letters matter. A French 5 francs piece carries a letter or symbol that identifies the mint: A for Paris, and other letters for Strasbourg, Lyon, Bordeaux, Rouen, Marseille and Lille at various periods. A collector who ignores the mint letter is ignoring a large part of the value difference between two otherwise identical coins.

The word "différents" covers the small privy marks, the mint master's symbols, that appear on French coins of the period. They change with the mint master, and they are one of the first things an experienced collector checks before buying.

A useful discipline is to write down the four facts for every coin you handle, even coins you do not buy. Country, date, weight, fineness. After a few dozen entries the pattern becomes visible, and the exceptions stand out.

4. What do the coins cost, and what does condition change?

Condition is the largest single variable in the price of a common coin, and the union series has plenty of common coins.

The French grading scale runs from FDC, fleur de coin, meaning essentially as struck, down through SUP, TTB, TB and so on to usée, worn. A 5 francs silver piece that is common in TTB can be scarce in FDC, and the price difference between the two can be a multiple rather than a percentage.

Catalogue prices are a starting point, not a valuation. They are usually quoted for a stated grade, and a coin that is one grade lower is not worth a fixed fraction of the catalogue figure. Auction results are the better evidence, because they record what someone actually paid on a given day, with the buyer's premium stated in the terms of sale.

For a beginner, the practical rule is to buy the best condition you can afford of a common date before buying a poor condition example of a rare date. The common date in high grade teaches you what an unstruck surface looks like. That knowledge is what protects you later.

5. How should you store and handle them?

Silver and gold are soft compared with the grit and dust on a normal tabletop, and a coin that is dropped or rubbed loses value immediately.

Hold a coin by the edge, between thumb and forefinger, never by the faces. If you must set it down, set it on a soft clean surface, not on wood or glass. Do not clean it. Cleaning removes the surface that graders and buyers look for, and an obviously cleaned coin is discounted even when the underlying piece is good.

Storage options range from paper envelopes and cardboard flips to capsules and albums. Paper and cardboard are cheap and fine for common coins, but they can tone a coin over decades. Inert plastic capsules cost more and do less damage. Albums with sliding windows are convenient for viewing and are a reasonable compromise for a working collection.

Keep the collection dry and out of direct sunlight. Humidity is the enemy of both silver and the paper records that give the coins their context.

6. How do you start a collection without wasting money?

Pick one series and one grade range, and stay inside them for a year.

The union series offers an obvious entry point: the 5 francs silver piece at 25 grams and 900 thousandths, and the 20 francs gold piece at 6.45161 grams. Both were struck in large numbers in several countries, both are widely catalogued, and both appear regularly at auction. A collector who learns these two coins thoroughly will recognise the same design conventions, the same mint letters and the same grading problems across the whole series.

Buy reference material before you buy coins. A catalogue with weights, fineness and mint letters will save more money than any single purchase. Read the auction terms before you bid, so that the buyer's premium and the shipping are part of your calculation rather than a surprise.

Keep a written record: what you bought, when, from whom, at what grade, and at what price. In five years that record will be more useful than any single coin in the box, because it will tell you what you actually know.

Finally, expect to make mistakes. The union series is well documented enough that mistakes are recoverable, and the documentation is the reason the series is a good place to learn.