China, the largest aluminium producer, is seriously lacking of reserves at the present and in the future. However, there are a huge amount of sub-economic aluminium resources (high iron diasporic, low A/S and high iron gibbsite and high sulfur diasporic bauxite), and potassic sandy shale suitable for the extraction of aluminium and the production of potassium and silicon fertilizers if proper metallurgical processes are developed. This study aims to investigate the sub-economic aluminium resources through investigation and identify the right technologies through laboratory tests for metal extraction and utilization of the by-products of K-feldspar sandy shale. The investigation of the sub-economic aluminium resources includes field and site visits and data collection and collation. A series of laboratory scale tests were carried out for different types of bauxite and potassic sandy shale, which includes initial try tests and formal laboratory experiments for optimization of the processes and procedures, and crop planting tests for use of potassium and silicon fertilizers. The successful laboratory tests (technologies) in this study were optimized and proved to be effective. The results showed: 1) Medium temperature metallization roasting and then magnetic separation, and gas reduction metallization roasting and then magnetic separation are effective for processing of the high iron diasporic bauxite; 2) Dry magnetic separation, wet magnetic separation and medium temperature magnetization roasting and then magnetic separation are not effective for processing of the high iron diasporic bauxite; 3) Digestion at atmospheric conditions and high caustic alkali concentration is effective for processing of low A/S and high iron gibbsite bauxite; 4) Desulfurization flotation and desulfurization with barium aluminate are both effective for processing of the high sulfur bauxite. However, each of these methods have their own advantages and disadvantages and must be evaluated; and 5) The soda-lime sintering process is suitable for processing of the Linzhou potassic sandy shale. The aluminium and potassium are extracted and the silicon residues can be used for silicon fertilizer. The results of this study help solve the problem of aluminium reserve shortage. They also open a new way for integrated utilization of other aluminium resources including potassic sandy shale.