A non-renewable resource is a resource of economic value that cannot be readily replaced by natural means at a quick enough pace to keep up with consumption. An example is carbon-based fossil fuel. The original organic material, with the aid of heat and pressure, becomes a fuel such as oil or gas.
Potential resources are resources which exist in a region and which can be used in the future. For example:- Mineral oil may exist in many parts of India where sedimentary rocks are found but till it is actually drilled out and put into use, it remains a potential resource.