The mining center of Tighza is located in the administrative region of Meknes – Tafilalet, in the Middle Atlas, 5 km from the town of M’rirt (90 km south of Meknes).
The farm occupies the center of an area of high hills rising to 1,494 m at Jbel Aouam, and between the trays of M’rirt southeast and Tanadra west.
Geologically, the mining center is located in the northeastern part of Hercynian Morocco. It is integrated in the evolution of the magmatic and hydrothermal events of the northern part of the Moroccan Meseta and is characterized by four granitic points and Pb / Zn / Ag / Au / W polymetallic mineralizations:
. Lead, zinc and silver in the form of MF veins, galena and silver blende
. Gold, vein or in skarns, bound to quartz and sulphides
. Tungsten stratoid and vein, in the form of scheelite and wolframite.
Key figures
. Annual production: 320 000 ttv, 25 600 t of Pb-Ag concentrates, 4 300 t of Zn concentrates.
. 3 seats in operation
. Hollow vein structures and rooting known from surveys over 1000m
. Staff: 300 people, including 25 executives
. Research budget: 35 to 50 million dh / year
. Annual investments: 40 to 45 million dirhams.
Ore extraction
The Tighza mine is underground and operates 3 veins: Signal, Ighrem Aoussar and Sidi Ahmed. Each of the three operating headquarters has two main wells, one for extraction and the other for service. These wells reach depths of more than 750 m.
The exploitation of the Tighza site currently uses three methods of exploitation, according to the morphology of the deposit and its geotechnical characteristics (land holdings, deepening of mineralization, width of mineralization, mineralization richness, water presence, etc. .).
The mining cycle at the Tighza mine can be illustrated as follows:
Production background – Extraction – Processing
The reserves and exploitable resources of the Tighza mining site, calculated at the end of December 2017, amount to more than 5,977 Kttv of ore. The average geological grades at the end of December 2017 are 7.54% for lead, 1.06% for zinc and 147 gr / t for silver. The research work carried out in parallel with the operation is intended to rebuild the reserves, prepare the mine and consequently extend the life of the mine site. These have made it possible over the last few years to restore them beyond exploited tonnages. Research work consists mainly of:
Geophysics and geochemistry from the surface.
Soundings from the day or from the bottom of the mine;
Mining works (galleries, wells and chimneys);
The evolution of resources and reserves between 2016 and 2017 is detailed in the following table (in Kt):