"Asteroid mining is the hypothetical exploitation of materials from asteroids and other minor planets, including near-Earth objects.[1]"
https://en.wikipedia.org/wiki/Asteroid_mining
"Asteroid mining refers to the extraction of minerals and other raw materials from minor planets and asteroids in outer space. Some of the raw materials found during asteroid mining include: silver, gold, platinum, rhodium, nickel, aluminum, manganese, iron, and cobalt (among others). Minerals and other materials mined in space could either be used in space as rocket propellant or as construction materials. Additionally, these materials may also be sent back to Earth for use and sale. Currently, however, the cost of asteroid mining and material transportation are prohibiting this practice. Techniques are still being developed and potential mining sites are still being researched. The demand for asteroid mining continues to grow as the natural resources on Earth become more and more scarce."
https://www.worldatlas.com/articles/what-is-asteroid-mining.html
"Asteroids could one day be a vast new source of scarce material if the financial and technological obstacles can be overcome. Asteroids are lumps of metals, rock and dust, sometimes laced with ices and tar, which are the cosmic "leftovers" from the solar system's formation about 4.5 billion years ago. There are hundreds of thousands of them, ranging in size from a few yards to hundreds of miles across. Small asteroids are much more numerous than large ones, but even a little, house-sized asteroid should contain metals possibly worth millions of dollars."
https://www.nasa.gov/content/goddard/new-nasa-mission-to-help-us-learn-how-to-mine-asteroids
"Of course, mining asteroids raises some legal questions. In the US, the law recognises that while you can’t own the Moon or asteroids, you can own the materials you take away from them – the same way you can’t own the ocean, but you can own the fish you take from it.
This means private companies could go into space, take materials they need, and it would be perfectly legal. The recent move by President Obama is seen as a huge step forward in terms of creating a stable legal framework to build upon.
Exactly where space mining could lead us is impossible to predict. But its advocates clearly believe that their early efforts are an investment in the long-term future of our species. We might not live to see the benefits, but our descendants spread throughout the Solar System may well be profitting from them"
https://www.bbc.com/future/article/20160103-the-truth-about-asteroid-mining
"Asteroids may be a much better place to get the supplies. Early evidence suggests that there are trillions of dollars' worth of minerals and metals buried in asteroids that come close to the Earth. Asteroids are so close that many scientists think an asteroid mining mission is easily feasible. Several international organizations are developing plans for going up to get these natural space resources"
"Corporations that might not be interested in exploring space for the adventure and science could be interested in the treasures that a space mining operation could send back to Earth. One NASA report estimates that the mineral wealth of the asteroids in the asteroid belt might exceed $100 billion for each of the six billion people on Earth. John S. Lewis, author of the space mining book Mining the Sky, has said that an asteroid with a diameter of one kilometer would have a mass of about two billion tons. There are perhaps one million asteroids of this size in the solar system."
https://science.howstuffworks.com/asteroid-mining.htm
"The advent of small and very inexpensive cubesats are a potential major boon for the space mining industry, says Kargel. Most of these new-type spacecraft are spin-stabilized and don’t last long, he notes. But the basic idea of having very inexpensive spacecraft which can be mass produced are fortuitous for future asteroid mining efforts, he says."
https://www.forbes.com/sites/brucedorminey/2021/08/31/does-commercial-asteroid-mining-still-have-a-future/?sh=6b82bb1a93f7
"Surely in the future the mankind will exploit the mineral resources of the Moon and other planets of our Solar System but, you know, to ensure the success of a mineral exploitation and exploration must be made before.
So, there is a question: the mineral deposits of, say, the Moon, have been already explored?
The deposits have been delineated and sampled, the resources have been measured by means of extensive drilling, feasibility studies have been made as to have proved reserves?
There exists enough information as to give to a mining company the sufficient level of confidence to begin a profitable exploitation?
I repeat, surely the mankind will exploit the mineral resources outside our planet, but I think it will occur on a far future… Without exploration, without the job of field geologists the mining operations are a nonsense, very risky and usually leading to the huge economic losses.
Today the idea of mining in space belongs to science fiction, but again, it will be possible in a far future."
https://www.911metallurgist.com/keep-mining/
The first crop of space mining companies didn’t work out, but a new generation is trying again
https://www.cnbc.com/2022/10/09/space-mining-business-still-highly-speculative.html