Photo source: Structural Stone
Full-size source sample visually checked against its named material page. Site-owner approval; photographer and producer-issued license are not documented.
Catalogue reference. Confirm the current range and finish with the supplier.
Material sources
Light gray granite from Rattlesnake Hill in Concord, New Hampshire, with a tight grain and small brown flecks. Historically known as Swenson Gray.
- Listed supplier
- Swenson / Polycor
- Quarry / operation
- Swenson Gray Quarry
- Location
- Concord, New Hampshire
- Color families
- Gray
- Supply route
- Dimension stone and curbing. Confirm current block availability, sizes and fabrication requirements.
- Listing source
- Producer documentation · source checked 25 Sept 2026
- Photograph
- Sourced photograph · checked 2026-09-25
Independent source checks
- U.S. material origin
- VERIFIED
- Material identity
- VERIFIED
- Producer relationship
- VERIFIED
- Quarry relationship
- VERIFIED
- Quarry location
- VERIFIED
- Operating record
- VERIFIED
- Photo source
- VERIFIED
- Photo permission
- SITE_OWNER_APPROVED
- Technical data
- REVIEW
Each check stands on its own. A photo or coordinate review does not change a confirmed material identity or producer relationship. Operating records do not guarantee current inventory.
Documented capabilities
Restoration and matching
Related producer groups
PolycorSource-described uses
Landscape & site stone
Uses described by the producer. This is not a finding of suitability for a particular assembly or project.
Application sourceQuarry origin
Swenson Gray Quarry
The material’s relationship to this quarry operation is confirmed.
Related quarry / permit records
Swenson Granite Company LLC
MSHA 2700083 · Active since 12/29/1982
Producer quarry identity and locality cross-checked with MSHAFind in quarry register View operation recordAsk the supplier about current availability, material range, fabrication and test data for your application. A listing or MSHA status does not establish supply readiness.
Published specification summaries are available; a traceable material-specific laboratory report has not been verified.
Swenson documents the Concord Gray / Swenson Gray identity and Concord quarry. MSHA records the quarry operator as Swenson Granite Company LLC, controlled by Polycor.