Mine mithril [723]
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Usage:  USE 723

Requires:  ten workers
Time:      7 days

Mithril is a magical metal used in the by the ancient
elf-lords to construct their bright, fearsome weapons.
Today mithril is the component of some rare construction
skills.

The character must be in a mine shaft to USE 723.  The mine's
monthly yield of mithril will be obtained.  Once mined, no
further mithril can be mined until the next month.

Use of this skill will cause the mine shaft to become one-third
of a level deeper.

The quantity of mithril obtained will vary with the depth of the
shaft.  Mithril is usually found only in very deep mines.  As
the dangers of poison gasses or collapse of the mine shaft increase
with depth, mithril mining tends to be risky.