Cheap Aluminum from Shuttle Tanks?

We don't have a practical way of using the Space Shuttle's expended External Tanks (ET) as quonset huts or habitats. But this does bring an idea to mind.

If we had an ET in LEO and about 130,000 lbs of propellants and a rocket motor, we could crash-land the ET on the moon. The launch costs for this amount of propellant is in the hundreds of millions of dollars range, although it is reduced by roughly a factor of 10 if a low-thrust, high-specific impulse transit happens to be a viable option by then for such a massive cargo flight.

For our trouble, we get a new crater plus 66,000 lbs of refined aluminum glopped up with some moon dust. The question is whether that puddle of aluminum is worth the cost of getting it to the moon, although this is one of the most inexpensive options for importing raw materials from Earth.