Natural Brown Diamond 5.20 ct Cushion – Untreated Cognac Loose Diamond

Looking for something truly different? Most engagement diamonds are white. This one is not, and that is precisely the point. At 5.20 carats, this natural brown diamond is a statement center stone for the buyer who has looked at conventional engagement rings and found them lacking. Its warm cognac-to-mocha colour, cushion cut and 9.7 mm square face create a presence on the finger that a white diamond simply doesn't. Brown diamonds read warm, earthy and personal, and they look extraordinary in yellow gold.

• Natural. Untreated. One of a kind. Made to be remembered.
• Natural earth-mined brown diamond, 5.20 ct, cushion cut, from African mines
• Natural fancy brown with cognac and mocha tones
• Completely untreated: never heated, irradiated, coated or enhanced in any way
• I2 clarity, honestly described: naturally included, with visible character
• Mohs 10, ideal for an alternative engagement ring or a men's signet ring
• A single loose natural diamond, sold unmounted. There is only one of this diamond.

An honest note on I2 clarity

I2 means the inclusions in this diamond are visible to the naked eye. We say this plainly because you deserve complete honesty. Natural inclusions are the geological record of how the crystal formed deep in the earth, and they are proof of natural origin. In a white diamond, inclusions compete with the colourless body of the stone. In a brown diamond, the warm body colour absorbs them, so they read as part of the stone's character, adding depth and a living, three-dimensional quality. The photos show this diamond exactly as it is, with no retouching or filters. If you want a clean, inclusion-free diamond, this isn't the right stone. If you want depth, warmth and a stone no one else in the world has, this is it.

The colour

Brown diamonds range from light champagne and cognac to deep espresso. This one sits in the rich middle: a warm, saturated brown with cognac highlights and darker mocha depths that shift as the stone moves. The videos are the best way to see it. Under warm indoor light, candles and evening light, the colour comes alive and the stone glows, with strong scintillation.

Why cushion cut

The cushion's softly rounded corners and brilliant-style faceting give a gentle, romantic light pattern that suits the warm, organic character of a brown diamond. At 9.7 × 9.7 mm, this cushion has a perfectly square footprint that reads bold and architectural face-up.

Completely untreated

Many brown diamonds on the market have been treated to change their colour. This one has not. Its colour comes from natural nitrogen and structural features formed as the diamond grew, so it is permanent and will never need re-treatment.

Who this stone is for

Couples looking for an alternative engagement ring, where a brown diamond in an 18K yellow gold solitaire, halo or bezel setting makes a ring you won't find in any store. Boho, vintage, rustic or outdoor weddings, where the stone suits the look perfectly. Buyers who find white diamonds too conventional. And goldsmiths creating a signature piece, where yellow gold gives maximum contrast, rose gold layers the warmth, and white gold or platinum gives a cooler, contemporary look.

Size and setting reference

At 9.7 × 9.7 mm, standard mounts made for 9 to 10 mm cushion stones will fit, and the 6.7 mm depth suits both bezel and prong designs. Full dimensional data is available on request for your jeweler.

A gemstone for him: the men's signet ring

At Roho Jewels, we believe men deserve beautiful gemstones too. A natural cognac brown diamond set into a signet ring is a bold, personal alternative to a plain metal signet: one-of-a-kind, full of character, and a ring he'll wear for decades and one day pass down.

• Signet face: at 9.7 × 9.7 mm, this stone suits a signet face of about 13–16 mm (most men choose a face of about 15–18 mm), great on the ring or middle finger
• Setting: flush (gypsy), bezel or half-bezel keeps it low and smooth, with no claws to catch on sleeves or gloves
• Depth: the stone is 6.7 mm deep, so ask your jeweler for a signet head at least 7.7 mm deep
• Metal: rich in yellow gold, sharp in white gold or platinum, rugged in oxidised sterling silver
• Wear: Mohs 10, the hardest gemstone on earth, made for a ring worn every day
• Perfect for: husbands, fathers, grooms, graduates, milestone birthdays, or a signet he buys for himself

Birthstone meaning

Diamond is the birthstone for April and has long been a symbol of strength and lasting love.

Common questions

Are the inclusions very visible? Yes, they can be seen with the naked eye, which is what I2 means. The photos and videos show the stone accurately. In a well-designed setting, the inclusions read as warmth and depth rather than flaws. Contact us for photos in different lighting.

Is the colour permanent? Yes. Natural brown colour is part of the diamond's crystal structure, not a treatment. It will look exactly like this for the lifetime of the ring and beyond.

Why this price for an I2 diamond? Because this is a 5.20 carat natural fancy brown diamond, completely untreated, at a size with real presence on the finger. In a brown diamond, the colour integrates the inclusions instead of exposing them. The price reflects the carat weight, colour depth and natural, untreated origin, not just the clarity grade.

Perfect for

Christmas Gifts · Alternative Engagement Rings · Statement Rings · Pendants · Anniversary Gifts · April Birthdays · Collectors · Heirloom Pieces · Men's Signet Rings · Gifts for Him

About Roho Jewels

At Roho Jewels, everything begins with the stone. Every natural gemstone we offer is hand-selected in our Toronto studio. These are real, earth-mined diamonds, sapphires, rubies, emeralds and pearls, never synthetics, and every stone is described honestly so you know exactly what you're buying. Our goal is simple: real gemstones, real craftsmanship and real value, without traditional retail prices.