In a Spanish wedding ceremony, the groom gives the bride 13 coins, called arras, to symbolize financial unity and that he now trusts her to carry his credit card without buying too many shoes. It's clearly a descendant of the traditional dowry. The jeweler that sold us our wedding rings threw in the arras for free. They are beautiful. Ours are from the Monarchs of Spain collection. I had no idea how hard it was to photograph gold coins. These are the best of several dozen attempts.
I think I've got them more or less organized chronologically.
Trying to capture beautiful gold color.
Click on this image to see the notes of all the kings and queens represented.
I'll give you one guess and three choices to why there are 13 of them:
The idea is that they are used in the ceremony and then kept as a family heirloom, possibly to be used by offspring on their wedding day.