| HN Mirror

Abundant in asteroids means that it is dissolved in solid iron at slightly more than 1 gram per ton of iron.

It is obvious that you cannot bring back to Earth a thousand tons of iron with the purpose of extracting from it a kilogram of iridium worth only a few thousand $.

Good luck for the extraction in the conditions at the surface of an asteroid of the kilogram of iridium that can be obtained by processing a thousand tons of hard iron alloy.

That would need a really huge amount of energy and processing methods that do not exist yet.

The average concentration of platinum-group metals in the Earth's crust may be lower by more than a thousand times in comparison with asteroids, but here these metals are not dispersed uniformly but they are concentrated in places where their concentration is similar or better than in asteroids.

Moreover in these mining places the platinum-group metals are present as metallic nuggets or as sulfide minerals, which are much heavier and with different chemical properties than the surrounding minerals. Therefore they can be separated cheaply.

Even so, the platinum-group metals are still only seldom separated directly, but usually they are obtained as by-product of extracting other metals, like nickel or copper, because they are more concentrated in the waste products than in the original ore.

At this stage, while the cost of transportation to and from an asteroid can be estimated with a reasonable uncertainty, absolutely nobody is able to estimate the cost in energy and chemical substances for the extraction of plantinum-group metals or of any other valuable elements while on the surface of an asteroid.

Until someone demonstrates on Earth a feasible extraction method, determining thus the amount of energy and of various chemical substances that do not exist on the target asteroid, which are necessary per mass of recovered valuable chemical elements, any commercial company that claims to have the purpose of mining asteroids can only be a scam for investors, because nobody knows if such an activity can become profitable before a remote future, e.g. one hundred years from now, when none of the present investors would remain alive.

I am pretty certain that some time in a not distant future the mining of asteroids will happen, but it will be mostly for substances easy to extract and easy to use in space, like steel for building structures outside Earth, not for bringing anything back to Earth.