Money

July is the best time to buy jewelry—here's what to know before you shop

Mindy Kaling (left) as Amita and Sandra Bullock (right) as Debbie Ocean in Warner Bros. Pictures' and Village Roadshow Pictures' "OCEANS 8," a Warner Bros. Pictures release.
Barry Wetcher | Warner Bros. Pictures
Mindy Kaling (left) as Amita and Sandra Bullock (right) as Debbie Ocean in Warner Bros. Pictures' and Village Roadshow Pictures' "OCEANS 8," a Warner Bros. Pictures release.

One of the best purchases you can make in July is jewelry. With no holidays in sight for the rest of the month, jewelry stores will be running promotions and discounts.

And there's no reason to wait for someone else to buy it for you. Celebrities like Venus Williams and Debra Messing who splurge on jewelry for themselves are part of a larger trend: Women now purchase roughly one in three pieces of diamond jewelry sold in the U.S. on their own, according to De Beers.

Shopping for jewelry should be fun, especially if you’re buying something special for yourself, Amanda Gizzi of the Jewelers of America tells CNBC Make It. “It’s all about going in to a jewelry store and really exploring, and finding something that speaks to you — jewelry is super personal,” she says.

Before you buy

1. Set a budget. Before you start looking around, have an amount in mind that you're willing to spend, or a ballpark figure at least. This will help you and whatever jeweler you’re working with narrow down the options and more easily find the right piece for you.

2. Find a jeweler you trust. No matter what piece you’re looking for, it’s important to shop with a reputable jeweler, ideally one you know and trust, since “they’re the ones who will be able to educate you if you need educating and they’ll be able to find the perfect piece for your budget,” Gizzi says.

Both Jewelers of America and the American Gem Society register jewelers and offer credentials like "Certified Gemologist" that ensure that staffers, whether at national chains like Zales or at small boutique shops, are ethical and knowledgeable.

If you’re planning to take advantage of the expected July sales online, the same advice applies: Shop only with retailers you trust. And because you can’t see the merchandise in-person, make sure you know and understand the return policy before you add anything to your cart.

When you're shopping

Here's what to keep in mind to help you find high-quality pieces as good prices.

Metals

The first thing to look at is the jewelry's foundation, which is usually the metal. “Anywhere you go, you’ll be able to see it’s marked with 14K or 18K or platinum,” Gizzi says. When talking about gold, the karats refer to the purity of the piece ("carat," on the other hand, refers to the weight of a diamond). For example, 24K gold means it’s 100 percent pure, while 18K means it’s 75 percent pure and 14K is about 58 percent pure.

Lower-karat gold tends to more durable, so 14K gold is a popular choice.

Popular metals like white gold and rose gold are made by combining gold with other alloys. Rose gold is made by mixing gold with copper. White gold typically contains nickel or a mix of palladium, zinc and copper. But despite the combo, white gold isn't usually white, so many times it’s plated with rhodium, a platinum group metal, according to Jewelers of America. That plating means you’ll need to give it some extra care to maintain the outer layer.

Often you’ll see diamonds and expensive gems set in platinum because it's most effective at securing stones, Gizzi says.

Diamonds

Many consumers are familiar with the four Cs of diamond shopping: carat, clarity, cut and color. While those are important, Ruth Batson, the CEO of the American Gem Society, says there are three additional Cs to keep in mind as well.

The first is the center stone. “It’s not only the focal point of jewelry, it’s where the majority of the money goes with the purchase,” she says. The other two Cs to keep in mind are custom and creativity. Not finding something that speaks to you? Don’t be afraid to go with a custom piece or a more creative look by utilizing a colored diamond or different metals like rose gold.

Pearls

“The majority of pearls you see inside a jewelry store are actually cultured pearls of some variety,” Gizzi says. That means they had a little human help — they’re still grown inside an oyster shell, but a molecule has been injected to speed along the process.

Natural pearls are very rare and so, if you do find one, the price will generally reflect that.

Two key components of a pearl are the luster, or shine, and shape. While perfectly round pearls are the most the most prized, and therefore the most expensive, baroque pearls, or those with a natural shape, are also popular right now. And the good news is they’re generally cheaper.

Gemstones

“Colored gemstones are having a moment,” Gizzi says. When shopping for gemstones, you’ll typically encounter three types: natural, synthetic and imitation. Natural, as the name implies, are those dug out of the ground. Like natural pearls, these are rarer, so they’re usually pretty pricey. Even if you do happen on a natural gemstone, keep in mind that many gems are treated, either with heat to enhance the color, or through the injection of colored glass or silicon.

More common are so-called “synthetic” gems. These aren’t fake but rather grown in a lab. Because they’re not as rare as natural stones, they’re generally more affordable. "Imitation" gems, by contrast, are the costume jewelry variety of stones typically made of glass.

Jewelers are required to disclose whether the gem is natural or synthetic and if it’s been treated, as that can affect how you need to care for it as well as the price. Using synthetic and treated gemstones in a piece can bring the cost down significantly. “A natural, untreated sapphire, for example, will be more expensive than a heat-treated sapphire,” Gizzi says.

“It’s a really great self-purchase because color really does speak to you,” Gizzi says. “You know what you love and so women feel empowered to buy on their own.”

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