Date(s) - 13/03/2024
7:30 pm - 8:30 pm

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Léonard Cornuz

Geologist, gemmologist and mineral enthusiast

The Aappaluttoq ruby deposit, an overview of gemstone mining in Greenland


Wednesday 13 March 2024, 7.30pm

(venue opens at 6.30pm for socialising and silent auction)



WA Lapidary and Rock Hunting Club Inc.
31 Gladstone Road, Rivervale


First described in the late 1960’s by the Danish geological survey GEUS, the Aappaluttoq ruby deposit is part of the Fiskenæsset Anorthosite Complex (FAC) in southern West Greenland. The Complex hosts several metamorphic/metasomatic corundum hard rock deposits over an ice-free length of over 200 km in Greenland and also on the east coast of Canada. In addition to being the oldest known corundum deposit known (2.71 Ga), the corundums of the Aappaluttoq ruby deposit are found in an unique geologic environment, inside a micaceous reaction zone between a mafic pod and a series of meta-leucogabbros, hosting a large set of varieties of corundum. Five years of surgical mining in the Aappaluttoq open-pit and of exploration in the surroundings have brought more insights about the formation of those deposits and links between the conditions of formation of the gemstones.


An MSc graduate from Lausanne University (Switzerland), Léonard Cornuz worked in hydrogeology/geotechnics before entering the mining industry at the Malmberget iron mine (IOA-type), Northern Sweden. After obtaining two diplomas in gemology (GIA, DUG), he joined the operations at the Aappaluttoq ruby mine for two years and conducted exploration of the surroundings. During the last months, he participated to a gemological tour around east Africa with Vincent Pardieu for a book project.