[1] Rough coloring techniques on the red stripe on the German bells may have caused the circles to appear as irregularly shaped dots, and French cardmakers may have decided to drop the details and straighten out the sides.

In older German-language accounts of card games, Diamonds are frequently referred to as Eckstein ("cornerstone").

The term "Karo" went into the German language in the 18th century from the French carreau, which goes back to the Latin word, quadrum, meaning "square" or "rectangle".

In the official Skat tournament deck, diamonds are yellow or orange, assuming the color of their German-deck equivalent, which are usually golden.

Not shown is the Knight of Diamonds used in the tarot card games: Four-color decks are sometimes used in tournaments or online.