The source you linked talks about uranium reserves. Mineral reserves, known and unknown deposits, refer explicitly to the known amount of economically minable supplies of that mineral.
Discussion around them can be misleading, especially for a growing industry, because as a resource becomes more scarce, it becomes more economically viable to mine difficult deposits, this growing the reserve. On top of that, the effort and technology tend to yield new methods of both mining and refining that increase yields.
The source you linked talks about uranium reserves. Mineral reserves, known and unknown deposits, refer explicitly to the known amount of economically minable supplies of that mineral.
Discussion around them can be misleading, especially for a growing industry, because as a resource becomes more scarce, it becomes more economically viable to mine difficult deposits, this growing the reserve. On top of that, the effort and technology tend to yield new methods of both mining and refining that increase yields.