It is quite simple to extract aluminum from nearly all rock and soil. Aluminum silicates are one of the most common minerals found in the Earth's crust.
Using a nickel or iron pot add sodium hydroxide pellets (as dry as possible) and heat until the alkali becomes a liquid. Add stones such as flint or dry soil, granite, basalt in small pieces. These will dissolve. Allow the mixture to cool then add pure water. The solution is an alkaline solution of the components. Add acid until neutral. A white precipitate of Aluminum Hydroxide occurs. Filter and wash. Heat to dryness. The result is aluminum oxide (bauxite).
Use the usual process of electrolysis of bauxite to recover Aluminum Metal.
It is possible to extract Iron from the remaining solution by first making the solution acid, (as you go to first to neutral the Aluminium Hydroxide in precipitated) at that point the silica precipitates filter out the SiO2, then making alkaline again and the Iron precipitates as a hydroxide.
The Silica may be processed to make Silicon for semiconductors.
Filter out this precipitate and heat and Iron II oxide may be collected for smelting into Iron and Steel.