Argyle Australian Champagne Diamond — 1.15ct Round Brilliant Cut| C7 - Dark Champagne

Why we chose this stone

C7 is the end of the line on the Argyle scale — the point where "champagne" gives way entirely to "cognac," a colour so deep and full it borders on chocolate in the right light. At 1.15ct, this round brilliant carries that grade at a genuinely rare intersection of size and saturation; stones this dark and this large were scarce even when the mine was still producing. The brilliant cut handles that depth of colour with real drama, breaking it into shifting pools of dark amber and warm flashes rather than one uniform tone, so the stone never reads as flat no matter the angle. It comes from the East Kimberley region of Western Australia, the source of every Argyle diamond mined before the pipe's closure ended production of this colour range entirely.

A C7 at this size sits at the very top of what the champagne-to-cognac scale can offer, and it's a look that doesn't try to imitate a white diamond in any way — it's meant to be the boldest, richest stone in the room. For collectors and buyers chasing genuine rarity within the Argyle range, a 1.15ct C7 is about as far as that scale goes.