The Brownstone Collection  ·  Black Pearl of Queens

Cognac & Champagne
Diamonds

Natural, warm, and completely unrepeatable — everything you need to know before you buy.

The Argyle Color Scale

From light champagne to deep cognac — C1 to C7

Developed by the Argyle Diamond Mine in Western Australia, the C1–C7 scale is the industry standard for grading champagne and cognac diamonds. C1–C4 covers the champagne spectrum. C5–C7 covers cognac.

Seven round brilliant cut diamonds showing the Argyle C1 to C7 color scale from pale champagne to deep cognac brown
Light Champagne Champagne Medium Dark Champagne Light Cognac Cognac Deep Cognac
← Champagne (C1–C4) Cognac (C5–C7) →

C5 – C7

What are cognac diamonds?

Cognac diamonds are natural fancy color diamonds that fall in the C5–C7 range of the Argyle color scale — a deep, warm amber-brown with orange undertones that resembles the color of aged cognac in direct light.

The color comes from structural deformation inside the crystal caused by intense pressure during formation deep in the earth. This graining effect changes how the diamond reflects light, producing the warm brown tones you see. Unlike nearly every other stone in fine jewelry, no two cognac diamonds are the same shade.

The exact color — how amber, how deep, how orange the undertone — is determined by the unique conditions of that individual stone’s formation. It cannot be replicated. Not even by another cognac diamond.

Loose cognac diamond C6, deep amber-orange, backlit on dark reflective surface
C6 Cognac Deep amber-brown · Orange undertones
Best with yellow gold, white gold & platinum
Loose champagne diamond C3, golden honey tone in cream velvet
C3 Champagne Warm golden-brown · Yellow undertones
Best with yellow gold & rose gold

C1 – C4

What are champagne diamonds?

Champagne diamonds sit in the C1–C4 range — lighter, more golden, with a yellowish warmth that catches afternoon light in a way that reads almost luminous. Think the color of the drink they’re named after: pale gold to deep honey, depending on the grade.

C3–C4 champagne diamonds have a noticeably richer, more pronounced warmth. C1–C2 are softer and more subtle — the choice for someone who wants warmth without intensity. Champagne diamonds pair with rose gold the way no other stone does — the two warm tones meet at the same frequency.

Unlike colorless diamonds, champagne stones are specifically sought out for their beautiful natural coloring. The more pronounced the color, the more distinctive the piece.

Natural vs Lab-Grown

Why natural? Why not lab-grown?

Lab-grown diamonds can produce fancy yellow and blue tones through chemical doping during the growth process. But the deep, complex warmth of a natural cognac or champagne diamond — the way the color shifts between amber, orange, and brown depending on the light — comes from physical graining of the crystal structure under geological pressure.

This structural characteristic cannot be engineered in a reactor at the same depth of color. A lab-grown brown diamond looks different from a natural one. For cognac and champagne specifically, natural is not a preference — it is the only way to get the real thing.

Billionsof years to form the color naturally
10Mohs hardness — same as colorless diamonds
2020Year the Argyle Mine closed — making these stones finite
0Lab processes that fully replicate natural cognac depth of color

How to choose your metal

The metal changes everything

The metal you set a cognac or champagne diamond in completely changes the character of the stone. Here is exactly how each of our five metals reads — and when to choose each one.

Cognac diamond solitaire rings in multiple gold metals on dark slate — Brownstone Collection by Black Pearl of Queens
New

14K Brown Gold

Our signature Brownstone alloy. A warm, earthy amber-brown that sits between yellow and rose gold. Stone and metal become one continuous cognac tone — nothing else in jewelry looks like this. Nickel-free. Skin-safe.

Best with: C4–C7 — all cognac & deep champagne
Most distinctive

14K Yellow Gold

Amplifies the warmth. Stone and metal become one continuous warm tone. The most editorial, fashion-forward pairing. Works beautifully with both cognac and champagne.

Best with: C1–C7 — all grades
Most popular

14K Rose Gold

The most romantic pairing. Champagne diamonds and rose gold share the same warm-pink frequency — the result is soft, luminous, and quietly luxurious. Best with C1–C4.

Best with: C1–C4 — champagne grades
Most romantic

14K White Gold

Creates striking contrast. The warm stone reads bolder and more dramatic against the cooler metal. Best for cognac diamonds where you want the color to announce itself.

Best with: C5–C7 — cognac grades
Most striking

Platinum

The premium contrast setting. Heavier and cooler than white gold, platinum makes cognac diamonds appear deeper and more saturated. The most formal pairing — chosen for pieces meant to last generations.

Best with: C5–C7 — deep cognac
Most formal

Western Australia, 1980s – 2020

The Argyle Mine — where the names came from

The Argyle Diamond Mine in Western Australia produced the majority of the world’s brown diamonds and was the source of most natural pink diamonds ever mined. In the 1980s, the mine began marketing its brown stones to jewelers using the terms champagne, cognac, and chocolate — replacing the industrial classification of “brown” with language that made the warmth of the stones feel luxurious.

The Argyle Mine closed permanently in 2020. Natural Argyle-origin diamonds are now finite. The color names, and the C1–C7 grading scale the mine developed, remain the industry standard for champagne and cognac diamond grading worldwide.

The mine’s closure in 2020 means that truly Argyle-origin cognac and champagne diamonds are now a finite resource. Every year, fewer of them exist on the market.

Argyle Diamond Mine, Western Australia
1983 Mine opens, marketing begins
1980s Terms “cognac” & “champagne” coined
C1–C7 Color scale developed & adopted globally
2020 Mine closes permanently

Market Context · 2025–2026

The De Beers Desert Diamonds campaign — and what it means

In October 2025, De Beers launched Desert Diamonds — their first major new product campaign in over a decade — built around natural diamonds in warm earth tones including champagne, sand, and blush hues. The bridal extension launched across the United States in April 2026.

The campaign confirmed what the colored diamond market has known for years: warm-tone natural diamonds are not a niche. They are a category. Consumer awareness of champagne and cognac diamonds is now at an all-time high.

19%Rise in colored diamond searches, Q4 2025
25MAmericans reached by the campaign
1B+Impressions across social, TV & out-of-home

Decision guide

Cognac or champagne? How to choose.

Choose Cognac if you want…

  • A stone that reads bold and warm from across the room
  • Striking contrast in white gold or platinum
  • A deep amber-orange tone with real presence
  • Something genuinely distinctive from any white diamond
  • A statement ring, signet, or pendant centerpiece
  • The most dramatic warm-tone in the collection

Choose Champagne if you want…

  • Warmth that works with everything in your wardrobe
  • A softer, more golden everyday tone
  • The best possible pairing with rose gold
  • A stacking ring that adds color without dominating
  • An engagement ring with personality but not provocation
  • A piece that reads warm and personal without being loud

Ready to shop?

The Brownstone Collection

Natural cognac & champagne diamonds set in solid 14K gold and platinum. Handcrafted in New York City. Made to order in your size and metal.

Shop All Brownstone →

Questions about stones, sizing, or custom requests? Text or call us at 929-806-1502