Any jeweler should be able to answer the black finger rhodium coating question, and do it for you if needed.
Earlier today I received a thought transmission:
EVERYONE, PLEASE SEND THE RINGS BACK FOR RHODIUM COATING! WHAT WITH THE TORN ROTATOR CUFF, FLU SEASON, LIFE IN GENERAL AND THE DEMENTIA JUST SETTING IN, COATING WAS JUST PLAIN FORGOT. SO SUE ME. NO WORRIES! AFTER I RECEIVE THE RINGS AGAIN, THEY SHOULD BE READY TO SHIP A SECOND TIME BY THE THIRD FRIDAY AFTER THE FOLLOWING FULL MOON, GUARANTEED! THANKS FOR YOUR CONTINUED PATIENCE, C