An Emerald anniversary
55th wedding celebration is Emerald.
An 150 year celebration is called a Sesquicentennial celebration
It is called a "centennial celebration"
A 100 year celebration is called a centennial celebration.
Don't know the answer?? It is a 55th birthday??? Yeah
60 year celebration
An 150 year celebration is called a Sesquicentennial celebration
Centennial
It is called Centenary.
Diamond Jubilee
It is a century or a centennial
Diamond Jubilee