Gemfields has this week announced the recovery of a 40.23ct rough ruby from its Montepuez deposit in Mozambique - described as one of the most important rubies unearthed in recent times.
The stone is said to set a "new benchmark" for the quality of rubies mined in Africa, with Gemfields reporting that its Montepuez mine has proven to be its most productive of all ruby deposits.
Gemfields owns 75% of Montepuez in partnership with local business Mwiriti Limitada, which has a 25% share.
As part of its efforts to be truly transparent, Gemfields will follow the stone's progress to eventually finding an owner. The rough stone will travel to Singapore to be part of Gemfields’ second ruby auction in December, where it will be sold to the highest bidder.
Given its significance, the gem has been appraised in advance of Gemfields’ December ruby auction in Singapore by leading gemstone laboratory the Gübelin Gem Lab in Switzerland.
Gübelin managing director Daniel Nyfeler said: “Although difficult to judge in the rough state, the transparency and colour of the crystal indicate an important gemstone might be cut from this piece of rough. We are looking forward to following the development of this remarkable rough from its current state to a cut gem."
Gemfields' first ruby auction in June this year generated US$35.5million (£20.9m), with the average price per carat totalling US$18.43 (£10.87).
The collection of 2.03m carats offered were also extracted from the Montepuez mine.