title: NAICS 21
text: # NAICS 21
  
  NAICS 21 is the category within the North American Industry Classification System which is composed of establishments that extract naturally occurring mineral solids(i.e. as metals, coal and other industrial minerals), liquid minerals (i.e. crude petroleum) and gases (i.e. natural gas).
  
  ## Definition of mining
  
  NAICS 21 uses the term "mining" to include quarrying, well operations, beneficiating and other mineral preparation customarily performed at the mine sites, or as a part of mining activity and distinguishes two basic activities:
  
  ### Mine operation
  
  Mine operation includes companies that operate mines, quarries, or oil and gas wells for themselves, and companies which operate them on a contract or fee basis.
  
  ### Mining support activities
  
  Mining support activities include companies that perform exploration (except geophysical surveying) and other mining services, on a contract or fee basis, with the exception of mine site preparation and construction of oil/gas pipelines.
  
  ## Further breakdown
  
  Companies are grouped and classified according to the natural resource which is or will be mined. Industries include establishments that develop the mine site, extract the natural resources, and/or those that process the mineral mined.
  
  ## Smelting and refining
  
  Smelting and refining take place in both the "mineral processing" (NAICS 21) stages and the manufacturing stages (NACIS 31-31).
  
  