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4.25ct Round Brilliant Cut, IF Clarity, D Colour Diamond Solitaire, Platinum Ring

£359,999.89 (inc VAT)
£299,999.91 (exc VAT)

Standard Delivery Included *

Item # 11658103
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This 4.25ct round brilliant cut, IF clarity, D colour diamond, solitaire platinum ring is a beautifully crafted luxury item. Internally flawless, this ring is unique and its 4.25ct diamond really sets off the piece – it really is exquisite in every possible way. The item comes with a Summation of Appraisal certificate from the International Gemological Institute (IGI).

  • Diamond Shape: Round Brilliant Cut
  • Minimum Diamond Weight: 4.25ct
  • Diamond Clarity: Internally Flawless (IF)
  • Diamond Colour: Colourless (D)
  • Metal: 950 Platinum
  • Size N makes purchasing the highest quality diamonds easy by offering the industry's very best diamonds at the lowest possible price. Our long-standing relationship with a number of approved suppliers guarantees we get the best selection of stones on the market. experienced buying team works closely with these suppliers to evaluate and hand-select each diamond for its quality and brilliance. Our team of Graduate Gemologists then inspect every diamond to ensure it meets the strictest quality standards; this includes a thorough examination of cut, colour, clarity, and craftsmanship. This way you can be confident your purchase is as special to us as it is to you.

This item comes with a Summation Of Appraisal certificate from the International Gemological Institute (IGI). This is to certify that the item described above is genuine, and has been independently examined in the laboratories of IGI.

Also included with this diamond is a GIA (Gemological Institute of America), Gem Trade Laboratory, Diamond Grading Report. Gem Trade Laboratory is a division of GIA Enterprises, Inc., a wholly owned subsidiary of the non-profit Gemological Institute of America, Inc. This describes the characteristics of the diamond at the time of the examination based upon 10 x magnification. 

When returning unique jewellery items, or items containing a 1.00ct centre diamond or larger, may require additional time to verify the diamond, in which case a refund will be approved upon positive verification and as long as the item is not damaged or changed in any way (i.e. resized or reset). This process may require two to five business days.

For any enquiries please email 

To view additional jewellery information click here.

Carat: 4.25ct
Clarity: IF
Material: Platinum
Colour: D
Cut: Round Brilliant


Delivery will take place via UPS insured. The estimated delivery time will be 5 to 10 business days from the time of order.
UPS tracking will be available 5 days following receipt of your order.

Additional day(s) transit may be required for remote areas.

These deliveries will require an adult signature.

Please note that we are currently unable to ship to the Channel Islands, Post Office boxes and BFPO.

Public and Regional holidays may affect delivery lead times.

Delivery times may vary in the event of adverse weather conditions.

Gift messaging is available during the checkout process.

We guarantee your satisfaction and want you to be happy with your purchase. If you wish to return an item or you would like to contact us, simply call our freephone number 0800 0324 324.

Please pack your parcel up securely, preferably using its original packaging, but removing the delivery label.

If the item arrived to you in a box, it will need to be in a box at the time of pick up.

In the case of jewellery items, refunds under the Costco Customer Satisfaction Guarantee and Refunds Policy will be subject to our positive verification of the item. Such refunds are also conditional on the item not having been damaged or changed in any way (i.e. resized or reset). This process may require seven to ten business days.

We regret that we cannot accept and process online purchase returns at any Costco Warehouses.

Find out more about our Delivery, Cancellations and Assistance Policy

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