GIA Certified

We exclusively propose diamonds certified by the GIA, the one and only grading authority for the diamond trade worldwide. Other laboratories over-grade stones, giving you a false sense of quality and value.

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100% Custom

The perfect engagement ring does not already exist in a display. It should be custom made with you, for you. Our onsite expert craftsmen will make that dream a reality.

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Friendly Support

At our studio, you will be treated in a private setting with all the focus on the making of your diamond purchase experience the most personal, relaxing, and educational diamond buying experience.

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Personalized Service

Our best engagement rings are created with a personalized service. The service begins with a consultation with Sevan, who will learn more about you and your inspiration, helping you to develop your ideas and final vision.

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A Brief History…

Design by Sevan - Custom Diamond JewellerySevan Tosun was born in 1977 in Istanbul, Turkey, the former capitol of the Byzantine and Ottoman Empires and home to a tradition of fine jewelry spanning over two millennia. At the age of 10, Sevan carried on his father’s legacy and began a full-time apprenticeship with one of the finest jewelry houses in Istanbul. By age 16, he had learned every facet of the trade, cultivating the highest level of skills a jeweler could achieve in metal, diamond setting and design, imagining intricate designs and creating pieces from start to finish.

With an amazing array of skills and dreams of a better life, Sevan left his roots in Istanbul as a teenager and headed for Canada with just $250 in his pocket. Connecting with a relative who had already emigrated to the Canada Sevan arrived in Toronto industry. Within a few years, Sevan developed a reputation as the finest jeweler in the area, and in 2000, he founded A.S.T.Jewelry ,Today, Design by Sevan  stands as one of the premier Engagement Ring boutiques in Fashion district Toronto.

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For many jewellers, making jewellery is a profession – for Sevan, it is an identity.

If an engagement ring design has caught your attention, make an enquiry with us today.

Specializing in Custom Diamond Engagement Rings

NO SALES PRESSURE SHOWROOM – No unwanted sales pressure. We promise!

  • Our trained consultants are NOT on commission. That’s what separates us from other jewellers. Feel free to come in and browse our store at your own pace. When you’re ready, we will be happy to answer any question you have.
  • Our personalized service focuses specifically on the customer. Visit our store and you’ll see we are truly on your side.
  • There’s no jewellery store better equipped to meet all of your engagement ring shopping needs.
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We specialize in designing custom diamond engagement ring, If you’ve got an idea for a ring or another piece of jewellery, we can help bring your idea to life and offer advice on the design and details to meet your individual needs.

We design all our engagement rings in-house and all commissioned rings are individually made for each client, this making us uniquely suited to offer customers great custom engagement rings at affordable prices.

Questions? Ask us anything.