pit limits

pit limits

[′pit ‚lim·əts]
(mining engineering)
The vertical and lateral extent to which the mining of a mineral deposit by open pitting may be carried economically.
References in periodicals archive ?
The ore reserves were reported based on mineral resources classified as Measured and Indicated within the economic pit limits above the economic cut-off grade after due consideration of costs and physical constraints.
We still have plenty of reserves in the pit--150 million tons, with an additional 270 million tons of resources including the stockpiles, and we're always expanding the pit limits, Stepper said.
Seabridge Gold Inc (TSX: SEA) (AMEX: SA), a Canada-based company that explores for mineral resources, has completed updated economic pit limits for the Mitchell, Sulphurets and Kerr zones at the KSM project.
433), and the recent results confirm that extensions to mineralisation exist at depths of up to 150 m beyond the planned pit limits in the Roby and North Roby zones.
In addition, these zones could allow for a wider pit dimension defined in the Preliminary Assessment completed last year which would extend project life by providing access to significant gold resources that currently fall below the designed pit limits.
Potential is also high for definition of higher-grade zones within the current pit limits, by infill drilling of areas previously drilled by widely-spaced exploration holes.
Most these pits were mined to less than 50m and have significant mineralisation outside the pit limits.
Although most of the ore is in Chile, the open pit limits extend into Argentina.
In addition, these zones could allow for a wider pit dimension which would extend project life by providing access to significant gold resources that currently fall below the designed pit limits.
A series of analyses was conducted to determine economic pit limits and the mining sequence for three mineral deposits in the Cobre Panama concession area: Botija, Colina and Valle Grande.
Most of these pits were mined to less than 50m and have significant shallow mineralisation outside the pit limits.
On present projections, this would support a 3 1/2 year operation and it is likely that this will be extended by exploiting at least some of the further resources of 2 Mt at 3 g/t gold equivalent contained in sulphide mineralisation directly beneath the presently defined open pit limits.