Other Places Minerals Are Found
Weathering processes break large rocks into smaller ones, in processes that can work on surfaces (immediately resulting in fine particles) such as sandblasting, or in processes that gradually turn large rocks into smaller and smaller ones, such as the freezing and thawing of water in pores or crevices which can divide a large rock in two.
Weathering can also include dissolving water soluble minerals, often followed by the precipitation of those (or related) minerals at another site. The precipitation can be caused by evaporation increasing the concentration of a chemical (yielding evaporites such as halite), by a change of temperature and/or pressure that decreases the solubility of a chemical (the process that yields most quartz crystals), by a change of chemistry (PH changes, oxidation, etc.), or by the action of living creatures such as diatoms (eventually yielding chalk or limestone beds).
The initial result of many weathering processes are
unconsolidated sediments, but these loose accumulations of material can also
form from volcanic processes. Over time, most unconsolidated sediments will
harden into sedimentary rocks.