Argyle Australian Champagne Diamond — 0.91ct Round Brilliant Cut| C5 - Medium Champagne

Why we chose this stone

C5 sits just past the midpoint of the champagne scale, deep enough to read as a genuinely rich gold rather than a light accent tone, without yet crossing into the darker cognac shades further up. At 0.91ct, this round brilliant gives that colour real scope to show — the brilliant's facet pattern breaks it into constant motion, so the stone flickers between deeper, more saturated flashes and brighter gold as it catches the light. It's a grade that tends to strike a balance buyers look for: distinctive enough that no one mistakes it for a white diamond, warm enough to feel luxurious rather than muted. It comes from the East Kimberley region of Western Australia, the source of every Argyle diamond mined before the pipe's closure ended that supply permanently.

Sitting just under a full carat, this is a stone with genuine substance, and a C5 grade gives it a depth of colour that holds its own as a centre stone without needing extra embellishment. It's a combination — solid size, confidently deep colour — that's becoming harder to find now that the source has run out for good.