What off-Earth resources? (was Because that's whethe people are)

OK you guys, we're back to the uploading again. Alright, I'll give you that
it'll happen, when it does, y'all are going to need lots of semi-conductor
and platinum group metals and silicates, as well as plenty of nickel-iron to
fashion your little circuit board minds and spaceship bodies, which brings
us back to the subject of what resources besides H and He we can find in the
'rest' of the solar system:

Spectroscopic studies suggest, and ground-truth' chemical assays of
meteorites confirm, that a wide range of resources are present in asteroids
and comets, including nickel-iron metal, silicate minerals, semiconductor
and platinum group metals, water, bituminous hydrocarbons, and trapped or
frozen gases including carbon dioxide and ammonia.

As one startling pointer to the unexpected riches in asteroids, many stony
and stony-iron meteorites contain Platinum Group Metals at grades of up to
100 ppm (or 100 grams per ton). Operating open pit platinum and gold mines
in South Africa and elsewhere mine ores of grade 5 to 10 ppm, so grades of
10 to 20 times higher would be regarded as spectacular if available in
quantity, on Earth.

Water is an obvious first, and key, potential product from asteroid mines,
as it could be used for return trip propulsion via steam rocket.
Professor John Lewis has pointed out (in Mining the Sky) that the resources
of the solar system (the most accessible of which being those in the NEAs)
can permanently support in first-world comfort some quadrillion people. In
other words, the resources of the solar system are essentially infinite And
they are there for us to use, to invest consciousness into the universe, no
less. It's time for humankind to come out of its shell, and begin to grow!!
Note that the asteroidal materials we are talking about are, simply, water,
nickel-iron metal, hydrocarbons, and silicate rock. Purified, and made
available in low earth orbit, they will be worth something like $500,000 per
ton, by virtue of having avoided terrestrial gravity's "launch cost levy."

These are values up there with optical glass, doped semiconductors,
specialty isotopes for research or medicine, diamonds, some pharmaceuticals,
illicit drugs. On the mining scene, the only metal which has ever been so
valuable was radium, which in the 1920's reached the fabulous value of
$200,000 per gram!

Platinum Group Metals (which are present in metallic and silicate asteroids,
as proved by the "ground truth" of meteorite finds) have a value presently
in the order of $1,000 per ounce or $30 per gram. Vastly expanded use in
catalysts and for fuel cells will enhance their value, and PGM recovery from
asteroid impact sites on the Moon is the basis of Dennis Wingo's book,
Moonrush.
http://www.nss.org/settlement/asteroids/key.html