Approach to hydrogen production through sulfide ores smelting has been discussed and a few comments on the treatment of sulfide ores based on the production and use of hydrogen have been made.

It would be safe to say that future developments in the field of hydrogen technology may possibly bring about a revolution in the field of metal extraction as we now know it. These developments may , in fact, cotribute to the fundamental solution of both energy and enviromental pollution problems. With this in mind, there should be no reason to wait for the emergence of a method for producing low-cost hydrogen。