Sterling popular silver carnelian agate brooch

This brooch looks antique,but it has a modern catch.
These were only invented in 1952 .
I can't tell if it is a replacement on an older brooch or a 1950s brooch.
Tv shape, which is clever if it was made before 1950s .
Lovely carnelian orange agate with bevelled popular edges
Stamped silver.
In very good condition.