The first thing on the list is; check the reputation of the jewelry store. Does it have a good or bad reputation? How are the reviews from clients? Are they more negative than positive? How the past customers describe the service and products remains the most important thing to check when buying for the first time. It is better if a trusted friend or family member referred the jewelry store. If not, better check their website for client reviews.
Remember, an established business would have excellent references on hand.