Copywrited
A c with a circle around it is the 'copyright' symbol.
It means the logo has a copyright.
The little c in a circle is the symbol for copyright.
If you mean the circumference or "perimeter": C = 2(pi)r, where r is the radius of the circle
Circumference refers to the size of something as given by the distance around it, e.g. the circumference of a circle is the distance around it, or its perimeter. The circumference of a circle can be used in the following formula to determine other values in a circle: C=2πr, or C=πd, where C is the circumference of the circle, r is the radius of the circle, d is the diameter of the circle and equivalent to twice the radius, and pi is, well, pi.
A c inside a circle means "with" in medical terms.
The size of something, distance all around it.Circumference is the distance around the perimeter of a circle.
GEMHK was a trademark used by Fredrick Goldman on fine jewelry between the years 2000 and 2007ish. Your piece also has a c in a circle meaning copyright
A c with a circle around it.
Copyright
copyright symbol is c with circle ©