Historically, the term Louis d'Or refers to gold coins produced between 1640 and 1792. As well as representing historical witnesses to the Ancien Régime, these coins tend to be rare and are true collectors' items.
 
Today, by misnomer, we call all gold coins minted in France "Louis d'Or", like the 20 franc Napoleon III gold coin, for example.
 
This week, let's discover the golden treasure of French monetary history.

The Louis d'Or : the evolution of a symbolic coin
 

In 1640, King Louis XIII decided to reform the French monetary system. The reasons that led to the creation of the Louis d'Or were primarily economic, with the aim of stabilising the royal currency and restoring the confidence of its subjects.
 
The sovereign sought to provide more cash to encourage and facilitate payments and also to stimulate safe-haven investments in the yellow metal. This was only made possible by the Edict of Saint-Germain-en-Laye, which promulgated the start of Louis d'Or production.
 
Louis XIII also waged war against the Spanish and British crowns: he wanted to eliminate as many foreign coins as possible from circulation on the French market. It was a way of restoring his authority, and let's not forget that coins were a propaganda tool, a demonstration of power. It was a powerful tool for asserting sovereignty over a territory.
 
The Louis d'Or was far from being the first French gold coin. In the time of Louis XIII, it supplanted the other gold coin, the Écu d'Or. Écus d'Or were struck by hammer, which explains why they are all different and may contain imperfections. 

In addition, the Louis d'Or was struck using a new technique known as the "balancier", the first industrial minting system to produce coins at a faster rate and with greater precision. It was one of the great technical innovations in economics and numismatics in 18th-century France. It was the work of Jean Warin, the general engraver of coins in Liège, who gave his name to a number of minting series.
 
A skilful and lasting reform, it was not until the Revolution that the Louis d'Or was dropped and gradually replaced by a new coin, the 20 Francs Napoléon I, which was 6.5 grams lighter and had a slightly lower gold content (900 thousandths).
 
In addition, the monetary system was reformed, switching to the Germinal franc system, with the first francs replacing the Louis d'Or and royal coins. The 20 franc module was in force from 1801 to 1914, although it should be noted that the term "Napoléon" came into competition with the Louis, creating confusion that remains today.
 
The price of a Louis d'Or is quite different from that of the Napoléon 20 franc gold coin, which is now a world-renowned investment coin adored by investors. 

Its price depends not only on the price of gold, but also on its numismatic appeal (rarity, mint, state of preservation, year of issue), all of which play a part in determining its price. So obviously a Louis d'Or is by definition rarer and therefore more expensive than a 20 Franc Napoleon.
 
It is much less easy to put a value on a Louis d'Or because they are harder to find: for a 'common' Louis d'Or you will need to spend just over 500 euros, whereas a rarer one will be estimated at several thousand euros.

Discovering Louis d'Or : the unique characteristics of Royal Coins

 
The difference between Louis and Napoleon gold coins

 
Although they are made of gold and are virtually the same size, Louis d'Or and 20 franc Napoleon coins are different in many ways. The value of the 20 franc Napoleon coins lies in their precious metal content, i.e. the yellow metal. In other words, they are worth the weight of gold they weigh. 
 
On the other hand, the Louis d'Or is a numismatic collector coin. Its value also depends on its weight in gold, its degree of rarity, its state of preservation and the number of copies minted in a given year, for example. 
 
Also, the first Louis d'Or issued under Louis XIII have a much higher value than the Louis d'Or of his descendant Louis XVI.
 
The quality, rarity and history of some Louis d'Or are historical testimonies and fragments of history, making them expensive and far more valuable than their weight in gold.
It should not be forgotten that numismatics and collector coins are also a way of investing.

The characteristics of a gold louis

 
As the spearhead of its economic reform, the Edict of Saint-Germain of 31 March 1640 ratified the creation of a new currency : the Louis d'Or, replacing the ecu d'Or. This coin weighed an average of 6.7 grams with a diameter of 25 millimetres and a gold content of 917 thousandths. 
 
The successors of King Louis XIII up to Louis XVI kept this coin and minted it in their effigy. The revolution marked the end of this coinage, which was transformed into the 20 franc Napoleon I coin from 1803 onwards. It was also known as the "Louis" coin until the First World War, which can sometimes lead to confusion.
 

The different royal currencies 

 
As part of his monetary reform policy, Louis XIII created three coins for everyday transactions : 
 

• The Louis d'Or or petit louis, weighing 3.376 grams and measuring 20 millimetres in diameter.
   
• The Double Louis d'Or, commonly known as the Louis, weighed 6.752 grams and had a diameter of 25 millimetres.
   
• The quadruple Louis d'Or, also known as the Double Louis, weighs 13.47 grams and has a diameter of 28.5 millimetres.

 
On the other hand, a series of other Louis d'Or were produced in small quantities; they were never intended to enter circulation and were objects of prestige, gifts for the most influential figures in the kingdom.
 
There were, for example, the 8 Louis, weighing 26 grams of gold, and the 20 Louis, weighing over 65 grams of gold. It is also the largest French gold coin ever minted, making it an exceptional object. They were also known as "pleasure coins" or "prestige coins" and had no economic purpose. The examples are convincing : two 8 Louis d'or coins were equivalent to the annual salary of a blacksmith.  
 
As they are extremely rare, they are highly prized : a ten Louis d'Or minted in 1640 by Louis XIII was sold for more than 700,000 Swiss francs by an auction house in 2019.

A highly prized numismatic collector's item

 
Numismatics is an interesting form of investment that is still little-known. For some years now, as part of alternative investment management, investors and international financial institutions such as banks have been taking an interest in the world of numismatics.
 
In these times of inflation and economic instability, investing in Louis d'or and numismatics is a way of combining passion with a safe-haven investment in gold. It's a way of taking an interest in French royal history and also acquiring gold. The price of coins has risen and fallen in recent years, as can be seen from the prices in the sales catalogues. In addition, numismatics and investment in Louis d'Or yield a return that exceeds the rate of inflation, since demand far outstrips supply in this area. 
 
Similarly, the role of the Louis in the French economy and numismatics is undeniable. It is the fruit of a major monetary reform ratified under Louis XIII, which marked a major turning point, that of a monarchic desire to mint and control the minting of good gold coins in order, as mentioned above, to drive out foreign currency and clean up the circulation of precious metal coins in the kingdom. 
 

It must be said that this was a great success, as the system lasted until the Revolution. Baroque France under Louis XIV also shone, and its prestige was affirmed in particular by the quantity of coins minted during the reign of the Sun King, who was a lover of antiquity and numismatics and minted a large number of types of gold Louis, finely reproducing his portrait over the years, or the specific features of the newly conquered territories.
 
Today, the Louis d'Or has become synonymous with the coinage of the kings of France and conjures up images of prestige: it is the Golden Treasure of French monetary history.
 
What's more, the most sought-after Louis d'Or is probably the 10 Louis D'or dating from 1640, and is often regarded as the most remarkable French gold coin. It is made of 917-thousandths gold and boasts extraordinary characteristics, measuring 50 millimetres in diameter and weighing more than 67 grams.

In recent years, these pieces have also fetched exceptional prices, as in 2012 at an auction house in Cannes, where one of them sold for over €200,000. These record prices are typical of extremely rare pieces, which in many respects are akin to works of art or prestigious objects worthy of collecting. 
 
As a result, the Louis d'Or is the great coin of French numismatics that has had an exceptional destiny and a notable longevity. It is no coincidence that the Louis d'Or is still spoken of and used in everyday language, even to the point of creating confusion.
 
It is the result of a monarchical reform that provided the kingdom with a strong gold currency.
 
Because of the historical evidence they have left us, these coins are rare and have great numismatic value. 
 
In this sense, despite the confusion that remains today between the Louis d'Or and the Napoleon, these two coins, as we have seen, are very similar. The Louis d'Or therefore represents the golden treasure of French history.