Gold Mining the Moon

The year is 2055 and a successful gold mining operation has been set up on the Moon.

Everything proceeded efficiently, while enhanced by the discovery of helium-3, until a nearly impenetrable metal plate, while buried three miles under the lunar surface, stops the profitable drilling.

After several failed attempts to cut through the plate, a way around it is sought, which provokes a technologically advanced alien species to defend their thousands of years, old, operation.
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A book from the quick read series.