Are you looking for the perfect oval diamond?

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Carat: 0.75ct
Color: D
Clarity: VS1
Price: ¥485,000

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Carat: 1.00ct
Color: F
Clarity: VS1
Price: ¥895,000

Tokyo's Oval Diamond Specialist

Are you looking for the perfect oval diamond?

Whether its for that once in a lifetime engagement ring, or that dream pair of oval shaped earrings - let Kensington use our years of experience to help find your ideal diamond.

We pride ourselves on being able to find our clientele bigger diamonds of the very highest quality, at a price that is hard to match anywhere in Japan.

Kensington Diamonds is Tokyo's specialist in larger carat size engagement rings, fancy shape and yellow diamonds.

You can find hundreds of oval diamonds, from 0.50ct to 5.00ct, in our inventory of over 10,000 GIA certified diamonds online.

Get in touch today and we will begin searching our contacts across the globe to find your perfect match.

Here are some of our most popular oval engagement ring designs, which one do you love the most?

The Elizabeth 1.00ct Engagement Ring, ¥995,000
Oval Diamond on Classic Platinum Setting F Color, VS2 Clarity
Carat Total Ring Price
(inc tax.)
0.50ct ¥380,000
0.70ct ¥530,000
1.00ct ¥995,000
1.50ct ¥1,950,000
2.00ct ¥3,050,000
Oval Diamond on Platinum Pavé Setting Fancy Yellow, VS2 Clarity
Carat Total Ring Price
(inc tax.)
0.50ct ¥415,000
0.70ct ¥560,000
1.00ct ¥1,025,000
1.50ct ¥1,980,000
2.00ct ¥3,080,000
Oval Diamond on Platinum Side Baguette Setting F Color, VS2 Clarity
Carat Total Ring Price
(inc tax.)
0.50ct ¥440,000
0.70ct ¥585,000
1.00ct ¥1,050,000
1.50ct ¥2,005,000
2.00ct ¥3,105,000
Oval Diamond on Platinum Halo Setting F Color, VS2 Clarity
Carat Total Ring Price
(inc tax.)
0.50ct ¥485,000
0.70ct ¥630,000
1.00ct ¥1,095,000
1.50ct ¥2,050,000
2.00ct ¥3,150,000

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Why are oval diamonds so popular?

Over the past couple of years, the oval diamond engagement ring was arguably the most popular design amongst Hollywood A-List celebrities. They are incredibly elegant and sophisticated in their appearance.

Oval diamonds are growing so quickly in popularity as they offer ladies a slightly different look, whilst maintaining the sparkle and brilliance of a traditional round solitaire diamond.

If you are looking for something that few other ladies in Japan own, then an oval diamond could be the perfect match for you.

Do oval diamonds really appear larger than round diamonds?

Oval diamonds have a larger surface area than traditional round diamonds - meaning if you looked at a 1 carat round and a 1 carat oval diamond next to one another, the oval would appear to be a slightly bigger carat size.

Many ladies looking to acquire the largest looking diamond possible are drawn towards the oval shape.

How do oval diamonds sparkle?

Ovals, like the traditional round, are also ‘modern brilliant cut’ diamonds meaning they have been cut and polished especially to give off as much brilliance, fire and scintillation as possible. (You could think of this as all the diamond's combined sparkle).

An excellently cut oval diamond will sparkle spectacularly across all its facets. The best way to guarantee you end up with the brightest diamond available, is to allow Kensington Diamonds to hand select you an oval with ideal cut proportions.

How are oval diamonds priced in comparison to other diamond shapes?

Oval diamonds and round diamonds are priced very similarly, meaning that ovals are the highest price per carat of the 'fancy' diamond shapes.

They are an extremely desirable shape, that are rare to see in Japan.

Why are yellow diamonds usually cut into an oval shape, and rarely ever round?

Oval diamonds have a large, wide open face (or 'table' as its known in GIA certifying terms) which means it is regarded as one of the best shapes to showcase a diamond's natural coloring. Rounds have smaller tables, hence do not refract these beautiful shades of colored light as well.

For this reason - Fancy, Fancy Intense, or Fancy Vivid yellow diamonds are usually cut and polished into either a oval or a cushion shape.

Why do I need to be wary of a 'bow tie' effect in oval diamonds?

Because of the way that oval diamonds are cut, there can sometimes be an uneven distribution of light, which casts a noticeable, dark shadow across the mid-section of the diamond.

Kensington Diamonds will select you an oval where the bow tie is largely invisible, and instead blends nicely into the sparkle of the diamond.

I want to use oval diamonds for a necklace or pair of earrings, is this ok?

Kensington Diamonds prides itself on being able to hand craft your perfect piece, whatever you are dreaming of. To get started, simply get in touch with us and we will be absolutely delighted to get your bespoke idea started as soon as possible.

The Imperial 1.34ct Engagement Ring, ¥1,095,000
The Duchess 1.24ct Engagement Ring, ¥1,050,000
1.32ct Oval on Pavé Setting, Please Inquire For Price
The Lancaster 1.06ct Engagement Ring, ¥550,000
The Elizabeth 1.00ct Engagement Ring, ¥995,000
Custom 0.70ct Oval on Kensington Lady Setting, ¥535,000
0.60ct Oval Diamond in Kensington Halo Setting, ¥520,000

Who are Kensington Diamonds?

Kensington Diamonds is a retailer of diamond jewelry based in Omotesando, Tokyo. We specialise in collections of engagement rings, eternity rings, tennis bracelets and earrings to suit every taste.

Our mission is simple:
To provide our clients with the very best quality diamonds, at a price few others can match in Japan.

If you are looking for a uniquely special diamond, hand chosen from the top 1% of the brightest available 'Triple Excellent' cut available worldwide - contact us now, and we look forward to offering our years of expertise to help you create your perfect piece.

How are you able to offer larger diamonds at a more reasonable price?

Kensington Diamonds sources the best diamonds directly from the world’s leading De Beers sightholder producers, cutting out any third party dealers. This allows us to provide our clients with the highest quality, at rates that appear extremely affordable in comparison to other high end retailers in Tokyo.

How can I be sure your diamonds are the real deal?

All our diamonds have been certified by the GIA (Gemological Institute of America) - known as the world's leading and strictest grading authority. It's color, clarity and cut ratings would have been vigorously tested before you ever see it - providing peace of mind your diamond will be of the absolute highest quality available anywhere in the world.

The GIA grading certificate (which outlines every conceivable attribute of the diamond) will be included with your finished piece, and it's unique GIA certification number lasered onto it microscopically.

Why are you appointment only?

We value our client's privacy, and pride ourselves on providing the absolute highest level of service in a comfortable, friendly environment at our showroom in Omotesando, Tokyo.

At Kensington Diamonds we believe that every customer deserves our full undivided attention, therefore we operate on an appointment only basis.

You will be welcomed in for a one-on-one consultation of up to one hour; where we will guide you exactly what to look for, over a glass of champagne. Explain how to get the biggest diamond available within your budget, and show you our most popular recent designs.

There is no absolutely pressure to purchase, and we are more than happy to answer any questions you have.

Where and how do you make your products?

Each and every product we produce is handmade here in Tokyo, by master craftsmen with decades of experience.

Our business is based on delivering beautiful, yet secure and sturdy pieces to our clients that will last a lifetime. We are exceptionally proud of the hours of world class Japanese craftsmanship that goes into each one.

What if im looking to buy a diamond ring for my partner, but I dont know her ring size, or what she actually wants?

We understand that most men enter the process of purchasing an engagement ring without knowing the first thing about either diamonds, or what their fiancé to be is actually hoping for...

Our job is to simplify the process for you entirely. At the consultation phase we will teach you everything you need to know about diamonds, happily answer all your questions, and offer recommendations based upon the information you provide us.

Over the next steps, we will work closely together until your finished engagement ring is exactly what she is dreaming of. Let us be your guide and do what we do best, which will in turn remove any stress or hassle from the process for you.

The Lancaster 1.06ct Engagement Ring, ¥550,000

How do I know your diamonds are ethically sourced and legal?

At Kensington Diamonds we abide by a strict code of conduct to ensure that every single diamond we sell our customers has been legally procured from an ethically responsible source.

We buy our diamonds exclusively from the world's largest and most-established producers, who are 100% compliant with the regulations laid out in the Kimberley Process. We are proud to be a morally responsible company.

Can I do a custom design?

Kensington Diamonds offers clients the opportunity to build a fully bespoke, one of a kind piece. If you have a unique idea in mind but no design experience, our creative team is here to help.

Allow one of our design experts to turn your concept into a fully detailed blueprint - before working with you every step of the way until we can deliver you your dream finished product.

Where can I quickly see all your recent creations?

Navigate to our Instagram profile @kensingtondiamonds where you will be able to see the 500+ beautiful pieces we have created for our happy clients over the years. This is a fantastic way to see what has been popular recently, and get some design ideas if you are still deciding which diamond shape, or ring design would be the perfect match for you.

If you care to follow us, we regularly update our profile with the designs from that week that really caught our eye.

And if you'd like us to, we'd be more than happy to feature your beautiful finished piece on our wall for the world to see once it is completed!

Do you have reviews online from previous customers?

We proudly boast a 5* review score on our Google business page, from happy customers that were over the moon to share the great experience that they had dealing with Kensington Diamonds with the rest of the world.

Our business is nothing without happy clients - so please take their word for it, not ours.

What is your post sales warranty?

We are very proud of our manufacturer's craftsmanship and ensure only the highest quality materials go into creating our jewellery. Therefore we are happy to offer a lifetime warranty to guard against any damage as a result of manufacturer defects.

What Happens at a Kensington Appointment?

At an appointment at our Omotesando showroom, you will be able to:

  • View or try on different diamond jewellery of all carat sizes until you find exactly what you are looking for.
  • Enjoy a glass of champagne/cup of tea, as you are welcomed to ask as many questions as you have to one of our diamond experts.
  • Benefit from our one-on-one advice of how to get a bigger, better diamond for your budget. We promise that even if you don’t proceed with us, you will receive extremely useful guidance on how to get the best diamond.

What happens if I don't find anything I like within the showroom?

We want you to enjoy yourself and leave our showroom with an experience to remember, regardless of whether you have purchased something or not.

If you don’t find the right option with us - that is no problem at all, and we wish you the best of luck with your purchase elsewhere.

We guarantee a friendly atmosphere, and there is absolutely no pressure to buy.

If you are interested in making an appointment then please get in touch now, and we will be delighted to welcome you soon.

Do you take precautions to stop the spread of Covid?

When you visit our showroom, you won’t need to interact with any other clients - it will just be your group and our diamond specialist, for a one-on-one consultation.

We always wear a face mask, keep a safe distance where possible, and take the utmost responsibility to clean and sterilise the office between client appointments.

Can I do a zoom appointment instead of visiting the showroom myself? Or can I buy online?

All our products are available to buy online through our e-commerce store.

However given the expensive, and sometimes bespoke nature of the beautiful products at hand - we understand most clients would like to see the diamonds with their own eyes before committing to purchase.

If for whatever reason you would prefer to arrange a consultation online instead of coming to our showroom yourself, we would be more than happy to facilitate this by scheduling an online Zoom call at your convenience.

What is your returns/cancellation policy?

After ordering your selected diamond, we offer all clients an appointment to visit our showroom and see the diamond for yourself. If for whatever reason it turns out to not be what you were expecting, there is no obligation to continue with the purchase and we will happily help you find an alternative from our other diamonds in stock, or cancel the transaction.

Upon confirming you want to proceed with the diamond purchase, customers are expected to pay a 50% deposit of the sale price immediately, and the remaining 50% upon collection of the finished piece.

A non-refundable 10% cancellation fee shall apply during the acceptable cancellation period of 48 hours after payment of the initial deposit. However due to the hand made, bespoke nature of our products - after 48 hours the sale cannot be cancelled and is considered final.

We always operate in good faith and aim to work with our customers to find a solution to any problem, however refunds will be made at Kensington Diamonds own discretion.

Do You Offer free resizing?

Classic platinum rings can be easily resized and we offer this service to our clients free of charge.

However care should be taken when ordering eternity rings or engagement rings containing a significant number of side-stones, as resizing may be more difficult and require re-setting.

If you are buying for a surprise gift for your partner, and do not know his/her ring size in advance - get in touch and we will do everything we can to help you find the correct size.

How long does it usually take to receive my finished product?

We aim to complete every piece within one month of ordering, as standard.

However if you are creating a custom design which will require a bespoke mould - the date of completion will likely be 5-6 weeks.

Regardless, if you are in a hurry or really need your piece to be finished by a specific date, we will happily work with you and offer options which can be delivered quicker if required.

Do you do ring repairs, or jewelry remakes for older pieces?

Kensington Diamonds only offers jewelry remakes, or ring repairs of pieces that we have created for a client. Unfortunately we do not commit to work with pieces created by other brands.

The Duchess 1.24ct Engagement Ring, ¥585,000

See how much more you get from Kensington:

To browse hundreds of oval diamonds, from 0.50ct to 5.00ct, in our inventory of over 10,000 GIA certified diamonds online

Browse through our 10,000+ GIA diamonds online

Let Us Help You Our job is to make this process as easy and straightforward for you as possible. Fill in the form below if you would like us to schedule a consultation with one of our diamond experts.

Please enter your name, email, desired product and ideal date and time of your appointment.

Past clients have rated us a perfect 5.0/5.0 on Google.



150-0001 Chou Chou Building 2B
4-24-24 Jingumae, Shibuya-ku, Tokyo, Japan


Omotesando Station (Chiyoda Line, Ginza Line, Hanzomon Line) Exit A2 Take the road in-between the Ralph Lauren building and Omotesando Hills, it’s a 2-minute walk. Look for the yellow building on your righthand side.

Open Hours

Mon-Fri 11:00 – 20:00
Sat-Sun 10:00 – 18:00
Appointment Only




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View more than 500 different diamond pieces we have created for our happy clients over the years, on our Instagram profile @kensingtondiamonds