Wedding Ring Tips

Are Costco Diamonds Good?

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    Diamond engagement rings and other jewellery are just some of the many items that can be found at Costco. You might not immediately think of jewellery and diamonds when you hear the phrase "Costco," but you might be curious about whether or not they are worth the price. How good are they, if at all? You'll have to read on to find out!

    Just where can one find the best prices? The solution is obvious: go to Costco! You undoubtedly shop at Costco frequently, and with good reason. The warehouse club has an incredible selection of goods for incredibly low costs. It may come as a surprise to learn that diamonds are one of the many items sold at Costco. However, how high-quality are those gems? The solution is provided by us. Try these top picks for the best wedding reception venues in Melbourne. Don't bother looking any farther, Boutique Event Group is here.

    History of Jewelry Sold at Costco

    Costco's reputation precedes them, so there's no need to research their past. Costco has many loyal consumers who are long-time shoppers there because they love the store so much. The Costco Wholesale Corporation has developed a brilliant strategy for making a profit by selling in bulk at low prices. Their customer service is unparalleled for a national retailer. And their return policy is unmatched in the industry.

    There was a time when Costco's jewellery selection was highly regarded. From the suppliers' point of view, quality assurance is their strongest suit. It appears that, in recent years, they've been compromising on the quality of their jewellery.

    A Knowledge of the 4Cs

    The 4Cs, which refer to colour, clarity, cut, and carat weight, are all standards developed by the Gemological Institute of America (GIA) and used by most jewellery stores to determine the value of gemstones. These factors are what give diamonds their quality grades. Although the cut itself is subjective, the quality of the cut does affect the shine.

    The clarity of a diamond is graded on a scale from flawless to slightly included. Grades range from very, very slightly included (VVS1) to included (VS1). The colour scale goes from "D" for "best" to "Z" for "worst," with "D" representing "colourless."

    All diamonds sold by Costco are guaranteed to be at least VS2 clarity and I colour. When you purchase a diamond ring from them and the centre stone is 1.00 carats or higher, you will receive a GIA Diamond Grading Report at no extra cost. With diamonds weighing over one carat, you can rest assured knowing that your investment is protected thanks to an independent appraisal from the International Gemological Institute (IGI).

    Tiffany & Co. (TIF) clients are not expected to decipher technical information independently. Tiffany has diamond specialists available for in-store, over-the-phone, and online consultations with customers.

    Variations in Diamond Costs

    Depending on these 4Cs, the quality of the setting, and the jeweller, the price of a one-carat diamond ring can vary from $3,800 to $29,000. As of April 2020, a simple stacking band set in 14k gold with a 0.08-carat VS2 diamond starts at $249.99 on the Costco website. The most expensive item currently available is a platinum ring featuring a 7.45-carat diamond with a VS1 clarity rating; it costs $364,999.99.

    Tiffany rings are not described using the 4Cs since the company uses secret techniques to make jewellery with stones. Diamonds, frequently set in clusters with other stones, adorn several of the rings seen on its website. Depending on the size, shape, and colour of the diamond you choose, the price of a solitaire ring can range from $14,000 and above.

    Blue Nile Inc. (NASDAQ: NILE) is an online diamond retailer that offers both loose diamonds and pre-set diamond rings, with one-carat stones starting at around $2,500. When purchasing a diamond from Blue Nile, customers are offered a number of optional mountings from which to pick at an upcharge. This publication employs the Gemological Institute of America's grading system.

    Service and Personalization

    Customers can personalise their jewellery purchases at traditional jewellery retailers. Numerous jewellers will create a one-of-a-kind piece for you if you find a stone in one ring but prefer the setting of another. Some businesses will even let you create your own custom ring by providing the materials and expertise to make something truly special from the description you provide.

    You can usually return to a brick-and-mortar jeweller from whom you bought a ring if it needs polishing, repairs, or if you want to have a gemstone removed from it and set into something else.

    There is no customization available for any of the diamond rings sold at Costco. Although ring sizes are provided in the product descriptions on the Costco website, you will still need to see a jeweller to get the band resized to your finger. Jewellery purchased from Costco will not be cleaned or repaired. Looking for wedding rings check out our list Wedding Ring Shops in Melbourne.

    Wedding Ring Tips

    Contextually, Speaking

    While Costco is great for picking up just about everything and still coming out ahead, its jewellery selection is lacking. A lack of employees diamond expertise was the first issue we encountered. After all, if you're going to be in charge of anything (in this case, diamonds), you should probably make an effort to get knowledgeable about it. Shopping for diamonds at Costco is a lot like grocery shopping for fresh food, but you still need to give some thought to a few things before making a final purchase. We bought a solitaire 0.70ct I VS2 round diamond to check its quality and evaluate how it stacks up against comparable diamonds on the market. The diamond's poor cut quality is immediately apparent.

    We were also interested in evaluating their 1.13-carat, G-color, VVS2 clarity, round, ideal-cut blue diamond in comparison to the Blue Nile's 1.13-carat, G-color, VVS2 clarity round, ideal-cut blue diamond.

    Fewer options

    Costco's diamond collection is the store's worst shortcoming. There are limited choices available. In contrast, the craftsmanship and diamond quality are acceptable. It would be wonderful if there were more variety for those who want a particular aesthetic. There are some positives to be said about Costco's selection of diamonds and wedding bands. In my opinion, their generous return policy is the store's best aspect when it comes to jewellery. If you're looking for a store with a generous return policy, go no further than Costco. An excellent feature is the lack of fuss involved in returning an item.

    Meaningful Value

    You may get the impression that Costco's rings and diamonds are of poor quality, but I'm here to set your mind at ease. But alas, high quality does not always translate to a lower price. For example, the 0.70 carat diamond, after taxes, will set you back roughly $3503.99. There seems to be something wrong here. That the cost is disproportionate to the value offered. A diamond's worth can be determined by whether or not its price is commensurate with its quality; in this case, it is not. An nearly identical diamond may be found at James Allen for $2610, a savings of 25%.

    The 1.13 carat ring sold by Costco online costs $24,800, but the 1.50 carat ring sold by Blue Nile achieves better light return because to a more offset crown and pavillion angle. Despite the fact that both diamonds are GIA-certified, the AGS Laboratory only accepts diamonds whose proportions fall within the range given by Blue Nile. Remember that the ring from Blue Nile cost only $11.301, a significant savings above the price at Costco. It's also important to note that Costco charges state sales tax on jewellery purchases, whereas online-only retailers typically offer ways to avoid this fee. Check out our post on What jewellery should a bride wear?

    A Look at Buying an Engagement Ring from Costco

    Costco is a fantastic warehouse club, but a terrible place to shop for jewellery. Neither the people nor the services offer any real additional value. The diamond is selected in the same way that one could select a bottle of shampoo or one of their delectable cheesecakes. The solitaire I VS2 round diamond that I chose was 0.70 carats.

    When purchasing a diamond from a local jeweller, we advise our readers to get in touch with us for personalised guidance. Calling us after perusing diamond rings at Costco guarantees you'll receive better, more in-depth guidance and recommendations from us and the online jeweller we suggest. That's the one thing a traditional storefront should be doing better than its online competitors. In this section, the Costco experience begins to show its flaws. The diamond didn't have a GIA certificate, and it didn't have a certificate of any kind.

    The diamond was cut nicely, and the clarity was around average. However, the diamond's actual colour was a J, not the I they had advertised. Explore the 4Cs of Diamonds to find out more about colour, clarity, and cut. In reality, the location was amazing despite its lack of complexity. An old-fashioned platinum ring with four prongs. The level of detail and quality was on par with any other provider I've worked with.

    Different Ring Settings and Designs Available at Costco

    Their lack of options also becomes a concern. Only about 15–25 items will be available at most stores. Fantastic quality and craftsmanship, but not much room for customization to suit your tastes. You can't find much variety in what they offer, even online. About seven different solitaire settings exist for round diamonds. On the other hand, James Allen only offers roughly 50 settings for their wide variety of rings, while Blue Nile's 66 solitaire options are quite staggering.

    Compare the Value of Diamonds at Costco


    The ring is pretty, but it's not worth what you'd pay for it. The total price, with tax, for the ring was $3,403.99. No matter how you slice it, the price is too much for what you get. My grade scale (J VS 2) and their grading scale (J VS 1) allow for two sets of comparisons to be drawn here (I-VS2).

    This platinum solitaire ring from James Allen features a stunning 0.70 carat J VS1 centre stone. This ring seems nearly identical to the one I saw, but it retails for $2,740, a savings of 25% when you factor in tax. Don't mistake our comparisons here as suggestions for what you should buy (though that is a great looking diamond). When searching for comparable diamonds, it is important to make direct comparisons. Contact us if you need guidance acquiring an engagement, and we will provide you with tailored recommendations.

    This 0.70 carat I colour VS2 clarity diamond will save you 28% if you go with their grading (despite the fact that they no longer use GIA certification). Blue Nile's cut is top-notch, and it looks beautiful in this solitaire mounting.

    When compared to other physical and mortar stores, those savings are substantial, but not as dramatic as they are when shopping online. It was especially noteworthy because Costco doesn't offer diamond services. There is no sizing service, no guarantee, and a little number of settings and diamonds to choose from. You can conduct some of your own investigating and checking at Costco, but you won't find any human interaction.


    Costco's diamonds may not be as good as they seem since they lack proper certification. When you buy a diamond ring from Costco that is under a specific carat, you only get Costco's own evaluation for insurance purposes, even though you would expect it to have been verified by IGI.

    Several reviews have mentioned that they did not receive the quality of stone they received, so it is strongly suggested that you have an expert analyse the stone. However, if a diamond doesn't come with any sort of certification, you should avoid purchasing it. More so when you think about how much you are overpaying for stones that aren't even certified, as evidenced by the aforementioned comparisons.

    We had a hard time tracking down the exact requirements that were used to award you the certification that you did. There's a note buried in the FAQs to the effect that "it all depends on the carat" (the unit of measure for diamond weight). All diamonds above 1.25 carats are accompanied by an AGS grading report and an IGI assessment certificate.

    Both are standard on all of their one-of-a-kind jewellery items, no matter the carat. Certificates issued by IGI are not as respected as GIA's because the former does not adhere to the same rigors requirements. However, they are still preferable to having a PhD gemologist on staff simply examine the stone, as is the case with smaller gems.

    I'm sorry, but you're going to have to try harder than this. Stores like Whiteflash and James Allen offer AGS and GIA certifications for even the smallest stones. You have a right to know the exact grade of the stone you are purchasing, especially because even a 0.9ct stone might cost several thousand dollars.

    One Must Make A Decision

    Since jewellery is just one of many departments rather than its own website, the selection is naturally more limited. However, a respectable number of attractive engagement rings can be found. In total, there are 77 different engagement ring collections and 56 individual engagement rings to pick from.

    You can pick out the stone yourself, though the mounting will be decided for you. Not only does this not make sense to me, but the fact that you can't even pick the metal for your setup makes me cringe.

    Also, Costco rings offer next to no sizing variety. All the rings are available in size 7, and some go up or down by one or two sizes. The rings can be resized in either direction by one size, but unfortunately, this is not a service offered by Costco.

    If you know exactly the preset ring you want, are shopping for someone with a finger size of 6, 7, or 8, and are in a rush, you will undoubtedly appreciate this narrowed selection. As we have shown, however, it often pays to look around before making a final purchase decision.

    Wrapping It Up

    There is no information on the ring's packing on the site, therefore more digging had to be done. No data was to be found there either. When it comes to getting down on one knee, nothing matters more than the box your ring came in. If you're thinking about making a Costco purchase, we suggest stopping by a local location and either asking to see the boxes in person or making a mental note to seek out a good box, depending on what you find.

    Statement Regarding Exchanges and Returns

    It takes some digging to find out what their return policy is for jewellery, as it varies from one to the next depending on whether you bought a ring or a washing machine. Underneath each item, however, we noticed a returns/warranty area.

    This appears simple at first glance, but there is no information provided regarding the time frame within which you must return your purchase. In most cases, you will have 30 days to return an item, but you should call the retailer to be sure.

    The item you've purchased is of the highest calibre and won't let you down. Yet, Costco is not even close to having the lowest price on high-quality diamonds. An authentic online jewellery store offers superior pricing and customer care, making it the best option whether shopping for an engagement ring or stud earrings. In addition, a diamond should never be purchased without a proper certification (like GIA or AGS).

    We really like Costco, but their jewellery section might use some work. A few examples of the various issues plaguing the company include a staff that is woefully uninformed about the products they are entrusted with, a lack of certificates, and a small range of diamonds. Though the quality and skill of the work is satisfactory, other considerations must also be met in order to deliver satisfactory service. Costco is not the ideal place to shop if you're looking to save money, which is strange given all the other ways in which they may help you save. We suggest checking out this web store as an alternative for the sake of comparison. Our highest honour, the 5 Diamond Award, has been bestowed upon them.


    Costco carries a wide variety of products, including diamond engagement rings and other jewellery. With such a large inventory and inexpensive prices, the warehouse club is a must-visit. When it comes to quality, how do those jewels rate? We at Boutique Event Group have the answer. An independent appraisal from the International Gemological Institute can provide you peace of mind when purchasing a diamond weighing over one carat (IGI).

    An each carat of diamond jewellery can cost anything from $3,800 to $29,000. The Costco jewellery department does not service or clean customers' purchases. The jewellery department's biggest feature is its fair return policy. More options for individuals seeking a specific style would be greatly appreciated. The total cost of the 0.70-carat diamond, after taxes and fees, will be about $3503.99.

    Blue Nile's 1.50 carat ring has an improved light return thanks to a more oblique crown and pavillion angle. Unlike most online-only merchants, Costco does not offer any means to avoid paying state sales tax on jewellery purchases. James Allen sells a virtually comparable diamond for $2610, a savings of 25%. The lack of certification for the diamonds at Costco raises concerns about their quality. Get in touch if you need help securing a contract, and we'll give you our expert advice.

    James Allen's platinum solitaire ring showcases a 0.70-carat, VS1-quality diamond. While the mounting will be determined for you, you will have the freedom to choose the stone. There are 77 ring collections and 56 unique rings to pick from if you're shopping for an engagement ring. These rings are easily resized up or down by one size, but regrettably, Costco does not provide this service. There is no mention of a return deadline or any policy information. You should call the store to make sure, but typically you have 30 days to return an item. When shopping for jewellery online, be sure you only deal with reputable vendors.

    Content Summary

    • Costco carries a wide variety of products, including diamond engagement rings and other jewellery.
    • In recent years, it seems like they've been selling jewellery of lower quality.
    • A GIA Diamond Grading Report is included at no extra charge when you purchase a diamond ring with a 1.00 carat or larger centre stone from them.
    • Diamond Price Fluctuations A one-carat diamond ring can cost anywhere from $3,800 to $29,000, depending on the 4Cs, the quality of the setting, and the jeweller.
    • A solitaire ring can cost anywhere from $14,000 and above, depending on the quality, cut, and colour of the diamond used.
    • Diamonds from Blue Nile Inc. (NASDAQ: NILE), an online diamond merchant, start at roughly $2,500 for one carat stones in pre-set diamond rings.
    • Blue Nile provides a selection of premium mountings for customers to choose from when purchasing a diamond.
    • The first problem we ran into was a simple lack of knowledge about diamonds among our staff.
    • There are fewer possible choices. The lack of a better diamond selection is the biggest problem with Costco.
    • On the other hand, the quality of the craftsmanship and the diamonds is adequate.
    • There are some bright spots to be found in Costco's bridal jewellery offerings.
    • Regarding jewellery, I think the store's excellent return policy is its strongest suit.
    • Simply said, Costco has the best return policy of any retailer.
    • Positiv Value Some people think Costco's rings and diamonds are of low quality, so let me put your mind at ease.
    • You should keep in mind that the ring you purchased from Blue Nile only cost $11.301, a huge discount from the price at Costco.
    • Costco Engagement Rings: An Analysis Although a great place to buy groceries, furniture, and electronics, jewellery is not one of Costco's strong suits.
    • We encourage our readers to get in contact with us for one-on-one assistance when making a diamond purchase from a neighbourhood jeweller.
    • Read up on the "4Cs of Diamonds" to learn about the importance of carat, colour, clarity, and cut.
    • Diamond Prices at Costco vs. Other Retailers Although the ring is attractive, it is not pricey enough to justify the asking price.
    • The ring cost a grand total of $3,403.99 after taxes.
    • The 0.70 carat J VS1 centre stone in this platinum solitaire ring by James Allen is nothing short of breathtaking.
    • Finding similar diamonds requires drawing parallels between them.
    • Costco's own appraisal is all you get for insurance purposes when you buy a diamond ring under a certain carat weight, even though you'd expect it to have been validated by IGI.
    • Since even a 0.9 carat stone can cost several thousand dollars, you have the right to know the exact grade of the stone you are purchasing.
    • While the mounting will be determined for you, you will have the freedom to choose the stone.
    • Since the site provides no details about the ring's packaging, further research was required.
    • Everything else is secondary to the packaging of your ring when it comes time to get down on one knee.
    • Disclosure Regarding Returns and Exchanges You'll need to do some research to figure out the store's return policy for jewellery, as it differs from one store to the next and even from the type of jewellery purchased (a ring versus a necklace versus a bracelet).
    • However, Costco does not sell high-quality diamonds at the lowest price.
    • Whether you're looking for an engagement ring or a pair of simple stud earrings, the best place to buy jewellery is through a reputable online jewellery store.
    • Although we love Costco, we do think they might do a better job in the jewellery department.
    • If you want to compare prices, you should check out this online shop instead.
    • They have been awarded our highest distinction, the 5 Diamond Award.

    Frequently Asked Questions About Diamonds

    Overall, Costco diamonds are of decent quality and offer great value, as long as they're GIA certified. You can find a ring for 50% less than at other big-name jewelry stores. But compared to online retailers, Costco cannot match their selections, customization, or service.

    Their selection is very limited, but the diamonds they do have are excellent quality. Overall you don't go wrong purchasing a diamond at Costco but you have more variety and options, as well as superior service and value shopping online at a reputable retailer like James Allen or Blue Nile.

    Costco offers our members high quality jewelry at an exceptional value. Our team of GIA Graduate Gemologists inspect every diamond to ensure it meets Costco's strict quality standards. We only sell natural and untreated diamonds.

    You can return most items, including jewelry purchased at Costco, after 90 days for a full refund or exchange. Costco has a risk-free 100% satisfaction guarantee as per its return policy that doesn't set time limits on the acceptable return period for items purchased at the warehouse.

    In the United States, for example, the national average for an engagement ring is around one carat. In the United Kingdom, it's 0.6 carats, and in Europe it's even smaller, hovering at 0.5 carats.

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