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A diamond engagement ring can be a significant expense for a couple and you want to make sure the ring is absolutely the perfect one for you. Perhaps you have inherited a family heirloom diamond, but want to change the dated setting. Or you have determined that you want to purchase a loose stone and select your own setting. Either way, doing some research and working with an experienced jeweler will help you end up with exactly the ring you want.

Take your diamond to a reputable jeweler and pay for an appraisal of the stone's quality and value. This is important information to have in case your stone is lost, damaged or stolen.

Ask the jeweler to show the two of you examples of the settings that would be appropriate for the size and shape of your diamond. Describe to him specifically what you are looking for, including the type of metal, a wide or narrow band, raised or set-in mounting and any other elements that are important to you in your engagement ring. Be realistic about what type of engagement ring your budget will support. According to Adiamor.com, the majority of couples select 18K yellow gold for its affordability, brightness and durability. Although platinum is heavier and more durable, it is considerably more expensive than gold.

Select the setting you believe will go with your stone and your eventual wedding band. An oval or marquis diamond may be perfect in a solitaire setting, while an emerald-cut diamond might look best set off by side diamonds. Some engagement and wedding rings are purchased in sets, but you may also select them separately. Ask the jeweler for his assessment about the feasibility of securely and attractively mounting your diamond in the setting you have selected.

Obtain a projected cost and completion date in writing from the jeweler for mounting your diamond into the selected setting. When the work is complete, make sure it is exactly what you requested; ask him to make any changes if needed to conform to your original specifications. If the bride-to-be is part of the selection process, get the ring fitted for her at this time. If you plan to present the ring to her at a later date or as a surprise, arrange for a return visit to the jeweler after you give it to her so she can have it fitted.

Maintain a copy of the appraisal and the receipt for the setting and mounting in your files for insurance purposes or in case something happens to the ring.