Named the “Kat Florence Lumina,” the 181.61-carat unheated gemstone carries an estimated value of HK$3 million to HK$5 million (roughly $386,000 to $643,500), making it one of the most significant Paraíba-type tourmalines to appear at auction in recent years.

The gemstone takes its name from renowned jewellery designer Kat Florence. Her husband, gem explorer Don Kogen, originally discovered the crystal in 2003 in Mozambique’s Mavuco district, located in Nampula province. Weighing an impressive 830 carats in its rough form, the gem remained untouched for years—despite early estimates that it could yield a cut stone of more than 300 carats.

At Florence’s urging, Kogen revisited the long-held crystal earlier this year. The initial cut produced a 315-carat gem, remarkable in size but lacking the desired brilliance due to a visual flaw known as “windowing”—a flatness that dulls the fire at the gem’s core, often seen in very large Paraíba-type stones.

To enhance its brilliance, the cutting team undertook a second, more refined cut, reducing the gem to 181.61 carats but dramatically improving its optical performance. The result is a vivid and luminous stone that stands out not only for its exceptional size but also for its clarity and colour saturation.

The Paraíba-type tourmaline, prized for its neon-like glow and rarity, is expected to attract significant attention from collectors and connoisseurs during the Hong Kong auction.