Since mining began here over 100 years ago, LKAB has produced over 950 Mt of ore, yet only one-third of the original ore body has been extracted. Since mid-1999, Kiruna s haulage level at a depth of 775 m has been replaced by the next level down at 1,045 m, which will support production until 2018. The operation employs 1,800 people, of whom 400 work in the mine. The Kiruna orebody was formed at around 1,600 Ma following intense volcanic activity with the precipitation of iron-rich solutions on to a syenite porphyry footwall.
Black ore contains less apatite than grey ore.
Components include the new automated rail transport system on the 1,045 m level, uprating the hoists and crushers, and increasing the ventilation system capacity. Seven 500 t-capacity shuttle trains, controlled from the 775 m level, collect ore from ten groups of ore passes, and deliver it to one of four crushing stations. The mine is divided into eight production areas, each containing its own group of ore passes and ventilation systems. Mining the 16.5 km of ventilation shafts was carried out by SIAB using Indau 500 raise borers, while Skanska Raise Drilling developed a total of 32 ore passes between the 775 and 1,045 m levels using Tamrock and Robbins raise borers. Alimak developed two special units based on its RCM-6 system to reinforce the ore passes with cable bolts and shotcrete as necessary.