A 700-year anniversary is called a "septcentenary." This term is derived from the Latin word "septem," meaning seven, combined with "centenary," which refers to a 100-year period. Celebrating such a milestone often involves special events or commemorations to honor the significance of the passage of time.
It is called silver or silver year.
A 100th year Anniversary is CAlled a Cenntenial .
A 100th year Anniversary is CAlled a Cenntenial .
A 300 year anniversary is called a tercentenary. A 400 year anniversary is called a quatercentenary. (be careful with the spelling of this one!)
A 70th Anniversary is called a Platinum.
Quasquicentennial
A 70th Anniversary is called a Platinum.
An Emerald anniversary
bicentennial
cotton
This would be your crystal anniversary.
Platinum year