Quinzième anniversaire
Joyeux quinzième anniversaire (it's the same sentence for a man or a woman)
15 th year anniversary
This would be your crystal anniversary.
Crystal is the primary material for the fifteenth anniversary with glass as the modern material and watches as the alternate modern choice.
Well the anniversary names are usually derived from gifts that are given on that year, for instance 1 year is paper, 10 years is tin, or aluminum, 15 is crystal, and 20 is china.
An anniversary falls on the same day every year, as it commemorates a specific date. For example, if a couple was married on June 15, they will celebrate their anniversary on June 15 each year. Leap years, which add an extra day in February, do not affect the date of annual anniversaries. Therefore, the specific day remains consistent annually.
quinze septembre
We say '15 heures' or 'Trois heures de l'après midi'. But '15 heures' is better.
J'ai quinze ans. Direct translation: I have 15 years. (I'm 15.)
The Titanic's 100th anniversary will be on April 15, 2012.
Sept heures quinze
I've seen this coin in good shape go for $11-15 on eBay.