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Our standard crafting time is 35 business days, with expedited options available if you need it sooner. (Fees apply.) Shipping time is additional. Find the estimated completion date and delivery estimate on the relevant product page, or visit our shipping or crafting timelines pages for more information.

Yes! We offer free express shipping on orders over 400 USD. We also cover duties and taxes for most countries. We recommend you check your shipping details carefully at checkout, as they can’t be changed once your order is confirmed. Visit our shipping page for more information.

Lab-grown diamonds – also known as laboratory grown diamonds or lab-grown diamonds – are real diamonds, not diamond simulants. They have the same chemical and physical properties as mined diamonds (also known as natural diamonds), offering the same brilliance, fire and beauty. The key difference is in their origin: lab-grown diamonds are created in a controlled laboratory environment rather than extracted from the earth.

Diamond simulants, by comparison, are materials that resemble diamonds but have different chemical and physical properties. Unlike a diamond simulant, a lab-grown diamond is a genuine diamond.

The only difference is their origin. Lab-grown diamonds are created in controlled laboratory environments using advanced technology replicating the conditions in which mined diamonds form. Both have the same chemical and physical properties and offer the same fire, clarity and carat weights as mined diamonds – only lab-grown diamonds are free from the ethical concerns associated with mining the earth.

We offer lab-grown diamonds in a wide range of shapes including round, oval, pear, emerald, radiant, cushion, marquise, elongated hexagon, princess, asscher, heart and elongated cushion. We also offer fancy colored lab-grown diamonds in a variety of shapes and sizes.

Whether you shop online or visit one of our showrooms, our specialist client advisors are here to guide and support you comprehensively from your first inspiration to your finished ring. In our showrooms you can compare gemstone shapes, carat sizes and compare ring designs with expert guidance, or even purchase from our ready-to-ship range. Online, browse our made-to-order and ready-to-ship collections, or enquire about creating a custom design.

We offer a lifetime manufacturing warranty on all rings – including engagement, wedding and fashion rings – for your confidence and peace of mind. All other fine jewelry, including earrings, chains, pendants and bracelets, is covered by a two-year manufacturer warranty. View our full warranty details.

Yes, moissanite is a beautiful, durable gemstone with exceptional brilliance, making it an excellent choice for an engagement ring. Though often compared with diamond, moissanite isn’t a diamond or ‘fake diamond’ – it’s a distinct gemstone with its own chemical and optical properties. Its intense sparkle, durability and more accessible price point make it an increasingly popular alternative to both lab-grown and mined diamonds.

As with all of our gemstones, Cullen moissanite is carefully quality-checked by our expert team. Read more about moissanite, browse our moissanite engagement rings, or book an appointment with our team to create a custom design.

You can visit Cullen showrooms in Austin, Houston, Los Angeles, San Diego and San Francisco. In 2027, we’ll also be opening new showrooms in North America.

Browse our showrooms or book an appointment to visit us in person. We also offer virtual appointments if you can’t make it to a showroom.

All Cullen lab-grown diamonds are carbon-neutral. This means the carbon emissions associated with their growth and manufacturing are offset through verified sustainability initiatives, resulting in net-zero carbon emissions. Learn more about carbon-neutral lab-grown diamonds.