by KATIE COLEMAN

When my now-husband and I got engaged 10 years ago, I was shocked to find out my engagement ring, with its gorgeous platinum band and near-flawless shimmering cushion-cut diamond center stone, was from Costco—the same place we get our rotisserie chickens and athleisure wear. However, I was even more taken aback when it was appraised for a third more than its initial cost. My experience isn’t out of the norm. In fact, it’s just one of the reasons why Costco’s jewelry department continues to—pardon the pun—shine.

From one-of-a-kind rings, earrings and necklaces to an array of gemstone jewelry, Costco leverages its buying power while working with fine-jewelry vendors specializing in gold, diamonds and gemstones. Rachel Reid, a Costco jewelry buyer, explains, “For us on the diamond side, we are able to leverage pricing through our vendor relationships, along with the volume we buy, in order to provide the best value and the best-quality diamonds.”

Kris Cramer, also a Costco jewelry buyer, has a similar approach on the gold side: “We find vendors that can support Costco’s quality, pricing, volume and production timelines. We want to offer better quality at a better price, which is really the crux of everything we do.”

Costco goes to great lengths to ensure the quality of all diamonds, pearls and gemstones it sells. Reid says the company employs almost two dozen Gemological Institute of America (GIA) graduate gemologists as part of its quality control measures.

“We have to pass a rigorous course on diamond grading, as well as identifying color stones, to receive a graduate gemologist diploma from GIA,” says Lisa Switzer, quality control manager and graduate gemologist at Costco. “This gives us the tools to be able to verify that our jewelry meets Costco’s high quality standards.” Many of Costco’s gemologists worked in the jewelry industry prior to joining the company, and Cramer and Reid stress that these individuals have brought valuable knowledge and experience to Costco’s quality control team.

Part of this quality is explained in detail in Costco’s online “Jewelry Buying Guide.” Cramer and Reid urge members to read the guide (costco.com/jewelry-buying-guide-diamonds.html) for an in-depth look at Costco’s strict standards for its jewelry.

Quality and value are very important aspects of any purchase, but when you buy fine jewelry, you want something that’s exceptional and special. “Costco’s co-founder, Jim Sinegal, would always say jewelry is one of those departments that sets the tone to the member, because it’s so unique in what we offer,” Cramer explains. “You’re not going to find a lot of pieces that we carry anywhere else.”

According to Reid, Costco sells one-of-a-kind necklaces, earrings and rings that feature gold, platinum, diamonds, gemstones and pearls. “Our unique jewelry offerings truly create a treasure hunt for our members,” she says. “And the elevated quality we carry rivals even the most high-end retailers, really showcasing the value Costco provides to our members.”

Thanks to Costco’s substantial buying power and efforts to provide the best possible items at the lowest possible price, Costco jewelry continues to lend a unique (and literal) treasure-hunt feel to members’ shopping experience. Cramer adds with a smile, “Seeing jewelry I helped pick out on our members is the best feeling.”