What is the legacy SIC equivalent for NAICS 212312?

NAICS code 212312 maps to the following legacy 1987 SIC codes: 1422 - Crushed and Broken Limestone.

212312 — Crushed and Broken Limestone Mining and Quarrying

Q: Is NAICS code 212312 valid in 2022?

Yes, 212312 is a valid 6-digit 2022 NAICS national industry code representing 'Crushed and Broken Limestone Mining and Quarrying'. This U.S. industry comprises (1) establishments primarily engaged in developing the mine site, mining or quarrying crushed and broken limestone (including related rocks, such as dolomite, cement rock, marl, travertine, and calcareous tufa) and (2) preparation plants primarily engaged in beneficiating limestone (e.g., grinding or pulverizing).

NAICS 212312 is 'Crushed and Broken Limestone Mining and Quarrying', a 2022 U.S. national industry under Sector 21 (Mining, Quarrying, and Oil and Gas Extraction); the SBA small-business size standard is 750 employees.

Description

This U.S. industry comprises (1) establishments primarily engaged in developing the mine site, mining or quarrying crushed and broken limestone (including related rocks, such as dolomite, cement rock, marl, travertine, and calcareous tufa) and (2) preparation plants primarily engaged in beneficiating limestone (e.g., grinding or pulverizing).

Overview Facts

NAICS Code	212312
Industry Title	Crushed and Broken Limestone Mining and Quarrying
SBA Size Standard	750 employees
IRS PBA Code	212310 (rolled-up match)
Sectors Hierarchy	Sector 21 → 212 → 2123
Source / Verified	US Census 2022 NAICS Manual / 2026-06-28

NAICS Structure: 212312 National Industry

Sector (2)

Mining, Quarrying, and Oil and Gas Extraction

Subsector (3)

212

Mining (except Oil and Gas)

Industry Group (4)

2123

Nonmetallic Mineral Mining and Quarrying

Industry (5)

21231

Stone Mining and Quarrying

National Industry (6)

212312

Crushed and Broken Limestone Mining and Quarrying

Legacy SIC Concordance

Trace the historical mapping chain from the 1987 Standard Industrial Classification (SIC) to the modern 2022 NAICS code format.

SIC 1422 - Crushed and Broken Limestone (via SIC1987:1422→NAICS1997:212312→2002:212312→2007:212312→2012:212312→2017:212312→2022:212312)

Related Resources & Compliance Guides

Further regulatory reference links for NAICS code 212312:

Sector 21 Directory Hub — List of related industries in the Mining, Quarrying, and Oil and Gas Extraction sector.
SIC ↔ NAICS Crosswalk Tool — Look up mappings between legacy SIC codes and modern classifications.
SBA Size Standards Guide — Complete rules and averaging periods for small business classifications.
Calculating Annual Receipts Guide — Detailed worked example of revenue calculation rules.
IRS Principal Business Activity Guide — How NAICS codes map to corporate and entity tax filings.

Related Industries in 2123

212311 - Dimension Stone Mining and Quarrying...212313 - Crushed and Broken Granite Mining and Qu...212319 - Other Crushed and Broken Stone Mining an...212321 - Construction Sand and Gravel Mining...212322 - Industrial Sand Mining...212323 - Kaolin, Clay, and Ceramic and Refractory...

Frequently Asked Questions (FAQ)

Is 212312 a valid 2022 NAICS code?

What is the SBA size standard for NAICS 212312?

The SBA small business size standard for NAICS 212312 is 750 employees (based on employees).

What is the legacy SIC code mapping for 212312?

NAICS code 212312 maps to the legacy 1987 SIC codes: 1422 - Crushed and Broken Limestone.