Vintage jewelry is now back in fashion like never before. Some women are discovering their mother's, grandmother's, or even great-grandmother's diamond necklaces pendants and taking them out into the light of day for the first time in decades. Others discover these pieces through retailers, auction sites, and estate sales.

Regardless of how you have discovered antique jewelry, there are some things you should know before purchasing (or selling) the piece. These are also general guidelines for people who are rediscovering their family's vintage gemstones, since understanding their value is essential.

First, it is important to get a diamond appraiser to take a look at your jewelry. An expert's opinion is essential, because there are many fake diamonds and other gemstones out there being passed off as the real thing. And unless you have the right training and equipment, there is no way to distinguish between a real and fake diamond.

Make sure that your appraiser gives you a written estimate of the jewelry's value. This is important even if you're just rediscovering your grandma's jewels because you will need this estimate for tax and insurance purposes. It will also provide valuable information about the quality and condition of the gems and whether they have any damage.

If you are buying antique jewelry as an investment, you need to know how much the piece is worth in today's market. The overall value depends on the value of the gems and precious metals in the piece, as well as the style and designer, and how the market values pieces of that type currently.

Many online sites and antique value books can help provide information about the market value of your diamond necklaces pendants. You can also hire an antiques appraiser with expertise in vintage jewels. Although there will be a small cost associated with this service, it may be worth it if you can more accurately know the piece's value.

Once you know the value of the vintage jewelry, including the values of the individual jewels, the precious metals that make up the piece, and its market value, vintage appeal, and popularity, you can make a decision about whether buying the piece will be a good investment.