Yelp is not a trustworthy source. I bought diamonds from Dioro Jewelers located in Dublin, CA and San Francisco, CA and was swindled by the owner Corinne. I got a GIA appraisal and it contradicted the paperwork I received from Dioro and the diamonds. Everytime I put up a review on Yelp for Dioro, it is immediately removed. I believe that Vendors can pay Yelp to remove negative reviews.