Value of a vintage lady's Gruen Gold?

[Solar]

Gents:

My wife is cleaning out the bedroom, and came across a lady's gold Gruen (u/k) how much gold, but there are apparent hallmarks in the metal on the reverse.

The bezel has stone chips; my dad's diamond tester seems to indicate the presence of diamond.

Its a Gruen quartz, in good clean shape from what I can see, and a scan is included.

Any ideas on value of this piece?

Thanks all,

Chris