| MPMaiden Plant | Maiden | NC | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MKMajestic Kitchen & Bath Creations - Wilmington | Wilmington | NC | Nonmetallic Mineral Product Manufacturing327212 | 1-19 | ◐ LIKELY ACTIVE |
| MFMaplewood (Wells Fargo) | Maplewood | MN | Nonmetallic Mineral Product Manufacturing327910 | 1-19 | ◐ LIKELY ACTIVE |
| MRMaricopa Ready Mix | Maricopa | AZ | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MMarion (Chesapkeake) | Iowa City | IA | Nonmetallic Mineral Product Manufacturing327910 | 1-19 | ◐ LIKELY ACTIVE |
| MPMartinsville Plant | Martinsville | VA | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MMMasons Mark Youngwood, PA | Youngwood | PA | Nonmetallic Mineral Product Manufacturing327390 | 1-19 | ◐ LIKELY ACTIVE |
| MMMASQ Masonry | Atlanta | GA | Nonmetallic Mineral Product Manufacturing327331 | 1-19 | ◐ LIKELY ACTIVE |
| MFMassachusetts Franklin 165 Grove St | Franklin | MA | Nonmetallic Mineral Product Manufacturing327991 | 1-19 | ◐ LIKELY ACTIVE |
| MRMattoon Ready Mix | Mattoon | IL | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MPMcCaysville Plant | Mccaysville | GA | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MMcMinnville | Mcminnville | OR | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MGMCNB Georgia Best Block | Cordele | GA | Nonmetallic Mineral Product Manufacturing327331 | 1-19 | ◐ LIKELY ACTIVE |
| MGMedway Granite Works | Medway | MA | Nonmetallic Mineral Product Manufacturing327991 | 1-19 | ◐ LIKELY ACTIVE |
| MMMemorial Monuments Salt Lake City | Salt Lake City | UT | Nonmetallic Mineral Product Manufacturing327390 | 1-19 | ◐ LIKELY ACTIVE |
| MCMerrill - CRM | Merrill | WI | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MCMesquite Concrete - Falls city | Falls City | TX | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MCMesquite Concrete - Skidmore | Skidmore | TX | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MRMesquite Ready Mix | Bunkerville | NV | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MWMFRD Willamette Graystone | Grants Pass | OR | Nonmetallic Mineral Product Manufacturing327331 | 1-19 | ◐ LIKELY ACTIVE |
| MMiddlesex | W. Middlesex | PA | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MPMiddletown Plant 181 | Middletown | OH | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MRMills River Plant | Mills River | NC | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MCMinneapolis (Japs-Olson Co) | Minneapolis | MN | Nonmetallic Mineral Product Manufacturing327910 | 1-19 | ◐ LIKELY ACTIVE |
MMC Materials Gulf Coast - Canal | Mobile | AL | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
MMC Materials - South Parkway | Memphnis | TN | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MMm-q | Atlanta | GA | Nonmetallic Mineral Product Manufacturing327390 | 1-19 | ◐ LIKELY ACTIVE |
| MNMooresville, NC | Mooresville | NC | Nonmetallic Mineral Product Manufacturing327991 | 1-19 | ◐ LIKELY ACTIVE |
| MCMorehead City | Morehead City | NC | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MMorgantown | Morgantown | WV | Chemical Manufacturing325120 | 1-19 | ◐ LIKELY ACTIVE |
| MRMorris Ready Mix | Morris | MN | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MCMoultrie County Ready Mix | Sullivan | IL | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MPMount Pleasant - Schmitz Read Mix | Mount Pleasant | WI | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MRM & R Ready Mix, Inc. - Delta | Delta | OH | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MRM & R Ready Mix, Inc. - McClure | McClure | OH | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MRM & R Ready Mix, Inc. - Pettisville | Pettisville | OH | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MRM & R Ready Mix, Inc. - Stony Ridge | Stony Ridge | OH | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MPMt. Pleasant | Mount Pleasant | PA | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MPMt. Pleasant | Mt. Pleasant | PA | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MSMt Savage Specialty Refractories - Ingomar | Ingomar | PA | Nonmetallic Mineral Product Manufacturing327120 | 1-19 | ◐ LIKELY ACTIVE |
| MGMurphy Granite Carving Inc. | Richmond | MN | Nonmetallic Mineral Product Manufacturing327991 | 1-19 | ◐ LIKELY ACTIVE |
| MPMurphy Plant | Murphy | NC | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MRMuskegon Ready Mix | Muskegon | MI | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MCMV Concrete | Mountain View | AR | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MMMWBQ - Midwest Block | Jefferson City | MO | Nonmetallic Mineral Product Manufacturing327331 | 1-19 | ◐ LIKELY ACTIVE |
| MRMYRCP Rinker Materials | Myrtle Beach | SC | Nonmetallic Mineral Product Manufacturing327332 | 1-19 | ◐ LIKELY ACTIVE |
| NFNaperville Field Office | Naperville | IL | Nonmetallic Mineral Product Manufacturing327390 | 1-19 | ◐ LIKELY ACTIVE |
| NPNaples Plant 16 | Naples | NC | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| NCNational City Cement Terminal | National City | CA | Nonmetallic Mineral Product Manufacturing327310 | 1-19 | ◐ LIKELY ACTIVE |
| NCNatural Concrete Products - PA location | East Butler | PA | Nonmetallic Mineral Product Manufacturing327331 | 1-19 | ◐ LIKELY ACTIVE |