Sterling Silver 925 SIGNED Diamond Key Shaped Pendant Necklace

Unique and beautiful 925 sterling silver pendant with accent diamonds key shaped with chain necklace. There are 10 total diamonds on the pendant. Diamonds are authentic and have been tested with the Diamond Selector I. Signed/Marked on back of pendant as "925 RJ" for sterling 92.5% silver and I think those are the letters it might be CI or something else hard to say for sure and the necklace is marked 4.24 grams 16” chain Pendant is almost 1.75” Stamped 925 on clasp Stamped 925 Italy on chain ends Stamped 925 and a makers mark which I can’t make out, maybe RJ It does test positive for diamonds on the presidium gem tester and positive for sterling silver