oops, didn't catch that mistake but you guys get the general idea; I'm just tossing a few figures around for the fun of it.
Here is another factoid, S. Africa mines chase gold veins deep into the earth, some as deep as two miles; all they do is drill ahead to find out which direction the vein is moving and blast in that direction, a technic I would think Silverado might be able to apply to digging out the Antimony once they locate the main feeder veins coming up from the earth's core with more future drilling.
$$ Ka-Ching Ka-Ching $$