THREE-D
Finds the three dimensional
open pit outline which maximizes the total undiscounted cash flow. It can be
used for mines with a life of up to three years. Beyond three years the
discounting of future cash flows starts to affect the ultimate pit outline
which has the highest Net Present Value.
FOUR-D
Deals with the effect of
time on the value of cash flows. It also allows rapid simulation of the mine
life for different mining sequences and economic scenarios. Four-D should be
used rather than Three-D when the mine life is expected to be more than three
years.
OPTI-CUT
Optimizes the cut-offs to
be used over the life of a mine so as to maximize Net Present Value.
FOUR-X
Analyses and forecasts the
optimal pit for long term projects. There is a single element version and a
multi-element version. It has all the facilities of Four-D, and operates in a
similar way. However, unlike Four-D it is not limited to handling just one
product. Four-X handles up to ten "elements", where each may or may
not be a product and each may or may not be the subject of a cut-off. Costs and
recoveries can vary with the grade of any of the elements. FOUR-X can be used
for project scoping, for feasibility studies, for sensitivity work, for risk
analysis, for scheduling, and for deciding where to drill.