Removing Black Stains from 9ct Gold Jewelry: Expert Advice

Question
I have a 9ct gold pendant and it has some black stains or some kind of dirt build up. I have tried cleaning it with warm soapy water and a toothbrush but had no success in removing the stains. Could you please advise me as to how I can clean the pendant, and what I should use. Thanks

Answer
HI MARIA,

YOUR BEST BET IS TO HAVE THE PENDANT POLISHED BY A JEWELER AND EXTENDED ULTRASONIC CLEANING. 9K GOLD CAN DISCOLOR BUT NOT NORMALY TO BLACK. IT IS ONLY 38% REAL GOLD SO SOMETIMES IT MAY TURN FROM LOCAL HOME CHEMICALS. IF YOU WANT TO TRY YOURSELF JUST DISSOLVE SOME TABLE SALT IN LEMON JUICE AND TRY THAT. DON'T LET IT SOAK IN THIS MIXTURE.    

AFTER IT IS POLISHED YOU MIGHT WANT TO GET IT ELECTROPLATED AND THEN IT WILL LOOK JUST LIKE NEW. GOOD LUCK.

PETER