The Friedrich d'or (French doré "goldener Friedrich (II.)") was a Prussian gold coin (pistole) nominally worth 5 silver Prussian Reichsthalers. It was used from 1741 to 1855 and since it was a silver standard regular issue coin and trade coin at this time, it had a different purpose to domestic silver coinage or Kurantgeld, the so-called window on the stock exchanges. It was normally traded at a small premium or discount to the face value of 5 thalers. In Prussian purchase contracts or bonds it was, due to its monetary usage, distinguished as the "preußisch Courant" or "Friedrich d'or".
Around 1780, for example, the Saxon August d'or had a price of 116 to 120 Groschen sächsischen Silberkurantgeldes, as a maximum discount of 4 Groschen. In the 19th century it usually had a low premium.
Modelled on the Spanish doubloon and French Louis d'or, the forerunner of the Friedrich d'or was the Wilhelm d'or. It was first minted in 1741 by Frederick II. It was continued by his successors Frederick William II, Frederick William III and Frederick William IV, until 1855. From 1747 a double Friedrich d'or was minted, and a half Friedrich d'or from 1749. Its fine weight sank in 1770 from 6.05 to 6.03 grams.
Other states, such as Saxony, were influence to mint an August-, Friedrich-August-, Christian- or Max d'or (after their rulers' first names). These gold and silver coins also instituted a temporary fineness in the coinage of the German states.
The Friedrich d'or was 21 carat gold. The fine weight was 6.032g. On the obverse was the king's head, and on the reverse was an eagle standing on its shield.