Surficial processes are the physical and chemical phenomena which cause concentration of ore material within the regolith, generally by the action of the environment. This includes placer deposits, laterite deposits, and residual or eluvial deposits.  Superficial deposits processes of ore formation include;
* Erosion of non-ore material.
* Deposition by sedimentary processes, including winnowing, density separation (e.g.; gold placers).
* Weathering via oxidation or chemical attack of a rock, either liberating rock fragments or creating chemically deposited clays, laterites, or supergene enrichment.
* Deposition in low-energy environments in beach environments.
* Sedimentary Exhalative Deposits (SEDEX), formed on the sea floor from metal-bearing brines.