Well, an easy way to start is simply talk to your friends. Find out where they've done business in the past, and if they were happy with their experience. A good jeweler understands that their reputation is incredible important to them, whether they're selling diamond engagement rings, pendants, earrings, or even watches. A good reputation leads to good word of mouth, which leads to more potential customers. They know it's important to keep their customers happy, and satisfied, so they'll go out of their way to make sure you have a great experience.
Once you've gotten the field narrowed down, all that's left is to actually check the places out. Look at the establishments, and talk to the jewelers. Make sure they're happy and willing to answer your questions, or to give you a quick education into the world of precious gem and metal grading. If they're more than willing to educate you, it shows that your overall experience is important to them, and you're not just someone to make a quick sale. Ask about cheap engagement rings as well, and see if they'll explain the differences, and what can make two seemingly identical diamonds differ greatly in price.
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