How's That In English?

welcome.

ain't language great ?

I think your question calls for a knowledge of heraldry: coin designs often include heraldic elements.
in English, "a square turned on a vertix" may be called a lozenge.
A shield on a lozenge is usually part of a larger design.
As I understand it, the lozenge signifies a feminine connection:
where two families are joined by marriage, the resulting coat-of-arms will show the bride's elements in lozenges.

Peter in Oz

Any of those phrases would suffice; "coat of arms on a lozenge" is probably best. In the peculiar pseudo-French language of heraldry, the word used is "lozengy"... but don't use that in everyday English. Wikipedia.