You can trust Costco to only offer the highest quality one-of-a-kind gemstones at the lowest possible price. Our long-standing relationship with our suppliers guarantees we get the best selection at the best value. Costco's experienced buying team works with our suppliers evaluating and hand selecting each gemstone to ensure it meets the strictest quality standards in the industry in cut, colour, clarity and craftsmanship. You can be confident your purchase is as special to us as it is to you.

We guarantee that all diamonds supplied by costco.co.uk are as follows: Clarity to be VS2 or better and colour to be "I" or better as outlined on the industry grading guide.