Name: Montepuez mine.

Location: Delgado province, in north-east Mozambique.

Mine Owner/s: Montepuez Ruby Mining (MRM), which is 75%-owned by Gemfields and 25%-owned by local Mozambican minority partner, Mwriti Limitada.

Brief Description:  Monetpuez is generally recognised as one of the world’s biggest known ruby and corundum deposits and the single biggest ruby producing mine.

The mine comprises several shallow, opencast pits split among? the Mugloto, Maninge Nice and Glass blocks. 

Brief History: The Montepuez deposits were discovered in 2009. Gemfields acquired 75% of the Montepuez mine  in June 2011, when a joint venture agreement was signed between Gemfields and Mwiriti, the original title holder.

MRM received a 25-year mining and exploration licence from the Mozambique government in November 2011, following which an amalgamation of concessions was completed, which is valid up to November 2036 and covering 340 km2.

Mining and exploration and have been under way at Montepuez since 2012.

Primary Metals/Minerals: Rubies.

Secondary Metals/Minerals: Corundum.

Geology/Mineralisation: The Montepuez concession is located within the wedge-shaped Montepuez complex, a junction between the north-south-trending Mozambique belt and the east-west-trending Zambezi belt. Both belts are known to be “treasure-bearing” and date from the Neoproterozoic Pan-African tectonic event.

Rubies from Montepuez differ geologically from many of the Asian rubies available on the international market, as the primary host rock is amphibole related, rather than marble or basalt related. The rubies around Montepuez are found in primary mineralisation, hosted within amphibolite, or secondary placer type, found in gravel beds.

Reserves: Total proven and probable reserves as at December 31, 2019, were estimated at 15.24-million tonnes grading at 9.1 ct/t.

Resources: Total indicated mineral resources as at December 31, 2019, were estimated at 15.3-million tonnes grading at 9.1 ct/t. Total inferred mineral resources were estimated at 30.11-million tonnes grading at 11.8 ct/t.

Mining Method: Montepuez is a conventional openpit operation using excavators, loaders and articulated dump trucks. Loaded trucks haul ore to stockpiles adjacent to the processing plant, while waste is backfilled into mined-out areas, thereby returning the area to its natural aesthetic.

Major Infrastructure and Equipment: The mine comprises a treatment plant, which includes a new thickener, a continuous feeding system and a slime treatment (centrifuge) facility that was commissioned in December 2019.

The mine includes a residential site, which has a clinic and modern gym, as well as various recreational and outdoor sports facilities.

Prospects: None stated.

Contact Details:
Gemfields
Tel +44 1481 731 554
Email gemfields@camarco.co.uk (on behalf of Gemfields)
Website https://www.gemfieldsgroup.com