| Site | Category |
| Jason Roberts & Associates | Advertising Agencies |
| Jewelers Network | Auctions |
| Jewelnet Auctions | Auctions |
| Jewelrytraders | Auctions |
| Jaffe, FD | Diamond Cutters |
| Johnathan Ichak | Diamond Cutters |
| J.I.B DIAMONDS | Diamond Dealers - Wholesalers |
| J.W. FINDINGS & STONES LTD. | Diamond Dealers - Wholesalers |
| J.W. HISTED DIAMONDS LTD. | Diamond Dealers - Wholesalers |
| jitendra impex | Diamond Dealers - Wholesalers |
| jitendra impex | Diamond Dealers - Wholesalers |
| JOGIA DIAMONDS INTERNATIONAL PTY LTD | Diamond Dealers - Wholesalers |
| Johnathan Ichak | Diamond Dealers - Wholesalers |
| Jonathan Stein | Diamond Dealers - Wholesalers |
| Jonathon Stein Wholesale Diamond Importers | Diamond Dealers - Wholesalers |
| Josef Herskovits & Co. Diamonds LTD | Diamond Dealers - Wholesalers |
| Joseph Blank Inc. | Diamond Dealers - Wholesalers |
| July Diamonds | Diamond Dealers - Wholesalers |
| July Diamonds | Diamond Dealers - Wholesalers |
| Jewelers Directory | Diamond Districts |
| Jewelry Online-Hong Kong Jewelry Manufacturers Ass | Diamond Districts |
| Joseph Blank Inc | Diamond Districts |
| J. Kleinhaus & Sons LLC | Diamond Manufacturers |
| J.B.& BROTHERS | Diamond Manufacturers |
| J.B.Brothers | Diamond Manufacturers |
|