I would not rush to call space the final frontier of profit:
Companies and investors are realizing that everything we hold of value — metals, minerals, energy and real estate — are in near-infinite quantities in space. As space transportation and operations become more affordable, what was once seen as a wasteland will become the next gold rush. Alaska serves as an excellent analogy. Once thought of as “Seward’s Folly” (Secretary of State William Seward was criticized for overpaying the sum of $7.2 million to the Russians for the territory in 1867), Alaska has since become a billion-dollar economy.
The same will hold true for space. For example, there are millions of asteroids of different sizes and composition flying throughout space. One category, known as S-type, is composed of iron, magnesium silicates and a variety of other metals, including cobalt and platinum. An average half-kilometer S-type asteroid is worth more than $20 trillion.
An average half-kilometer S-type asteroid is worth more than $20 trillion? An average half-kilometer S-type asteroid, if it’s a 500-meter-diameter sphere, is 65 million cubic meters in volume and, at 3000 kg/m3, 2×1011 kg in mass — 200 million metric tons. So a “valuable” asteroid is worth $100,000 per metric ton. That’s 200 times the value of slate here on earth — which doesn’t seem like it would justify the freight costs.