NAICS 327992

Overview

The North American Industry Classification System (NAICS) is the federal statistical standard used to group business establishments for the collection, analysis, and publication of U.S. economic data. Developed by the U.S. Economic Classification Policy Committee with Statistics Canada and Mexico’s INEGI, NAICS replaced the SIC in 1997 and is updated on a roughly five-year cycle, with the latest vintage being 2022. ¹

U.S. industry NAICS 327992 (Ground or Treated Mineral and Earth Manufacturing) covers establishments primarily engaged in calcining, dead burning, pulverizing, or otherwise processing beyond beneficiation clays, ceramic and refractory minerals, barite, and other miscellaneous nonmetallic minerals. Basic crushing, grinding, washing, screening, and sizing performed at the mine site are classified under Mining NAICS 2123. Census economic programs use this industry definition for 2022 NAICS statistics. ²

What this NAICS covers

• Calcining or dead-burning clays and refractory minerals beyond beneficiation. ²
• Chemical or thermal treatment of barite and other nonmetallic minerals beyond basic preparation. ²
• Processing of ceramic and refractory mineral feedstocks that alters composition, purity, or properties (beyond simple crushing, grinding, or sizing). ²
• Manufacturing ground or treated minerals and earth when performed away from the mine site. ²
• Establishments whose principal activity is processing nonmetallic minerals for downstream industrial use, when work exceeds beneficiation. ²
• Operations classified in Manufacturing rather than Mining when heat, chemical, or other processing goes beyond beneficiation. ²

Related NAICS and PSC codes

Type	Code	Descriptor
NAICS	327991	Cut Stone and Stone Product Manufacturing
NAICS	327993	Mineral Wool Manufacturing
NAICS	327999	All Other Miscellaneous Nonmetallic Mineral Product Manufacturing
PSC	9350	Refractories and Fire Surfacing Materials
PSC	9610	Ores
PSC	9620	Minerals, Natural and Synthetic

Scope notes and cross‑references

• Excludes crushing, grinding, pulverizing, washing, screening, and sizing performed at mine sites; those beneficiation activities are classified in NAICS 2123. ²
• Includes the manufacture of ground or treated minerals and earth when the processing occurs away from the mine site or goes beyond beneficiation. ²
• Falls within Manufacturing sector 31–33, Subsector 327 (Nonmetallic Mineral Product Manufacturing), industry group NAICS 32799. ²

Frequently asked questions

• What activities qualify under NAICS 327992?
  Establishments that calcine, dead burn, pulverize, or otherwise process beyond beneficiation clays, ceramic and refractory minerals, barite, and similar nonmetallic minerals are included. Basic crushing, grinding, washing, screening, and sizing at mine sites are excluded. ²

• How is NAICS 327992 different from Mining NAICS 2123?
  Mining NAICS 2123 covers extraction and on-site beneficiation (e.g., crushing, grinding, screening). NAICS 327992 applies when processing goes beyond beneficiation (such as calcination or chemical treatment) and constitutes manufacturing. ²

• Were there 2022 NAICS content changes specific to NAICS 327992?
  The Census implementation resources describe the 2022 update and adoption timeline, but do not identify a code-specific change for 327992. Not specified by official sources. ³

• What products or materials are typical under NAICS 327992?
  The definition cites clays, ceramic and refractory minerals, barite, and miscellaneous nonmetallic minerals processed beyond beneficiation. It does not provide a canonical product list; specifics vary by establishment and application. Not specified by official sources. ²

• Which PSCs are commonly paired with awards for ground or treated minerals?
  Depending on the predominant item purchased, agencies may use commodity PSCs such as 9350 (refractories), 9610 (ores), or 9620 (minerals). Final PSC selection follows the PSC Manual’s predominant product guidance. ⁷

Useful resources

• G2X — NAICS 327992 overview
• U.S. Census Bureau NAICS detail for 327992 (industry definition and cross-references). ²
• Census implementation of 2022 NAICS (vintage and adoption timeline). ³
• Economic Census by Industry tables (NAICS-based statistics). ⁵
• Economic Census: Understanding NAICS. ⁶
• Product and Service Codes (PSC) Manual (current edition). ⁷

References

1. U.S. Census Bureau — Classifying Businesses (history and overview of NAICS). https://www.census.gov/about/history/historical-censuses-and-surveys/census-programs-surveys/economic/classifying-businesses.html
2. U.S. Census Bureau — 2022 NAICS detail for 327992: Ground or Treated Mineral and Earth Manufacturing. https://www.census.gov/naics/?input=327992&year=2022&details=327992
3. U.S. Census Bureau — Implementation of the 2022 NAICS. https://www.census.gov/library/reference/code-lists/naics/2022/implementation-timeline.html
4. U.S. Census Bureau — Economic Census by Industry tables. https://www.census.gov/programs-surveys/economic-census/data/tables/industry.html
5. U.S. Census Bureau — Economic Census: NAICS Codes & Understanding Industry Classification Systems. https://www.census.gov/programs-surveys/economic-census/guidance/understanding-naics.html
6. U.S. General Services Administration — Product and Service Code (PSC) Manual, April 2025. https://www.acquisition.gov/sites/default/files/manual/PSC%20Manual%20April%202025.pdf