ForMatter/Materials/stone/Granite
mat_granite

Granite

igneous stone — coarse-grained intrusive · dimensional granite, engineered granite (cut stone)
mediumlast updated 2026-04-28

Magma cooled slowly underground until its three minerals — quartz, feldspar, mica — crystallized big enough to see with the eye. Hard, heavy, polishes to a glass-like sheen, lasts forever in any climate. Kitchen counters and cemetery monuments share the same stone. Color is whatever the local quarry is.

Coarse-grained intrusive igneous rock, typically 65–75% feldspar + quartz + mica. Compressive strength 130–260 MPa, tensile ~7–25 MPa. Mohs 6–7 (steel won't scratch it; quartz will). Polishes to a mirror finish; the mirror is the proof of mineral grain. Geographic origin dominates color: Sardinia red, Maine gray, Brazilian black (the last is technically gabbro, sold as black granite).

Mechanical

  • compressive strength · MPa200
  • tensile strength · MPa15
source: Wikipedia — Granite; building-stone literature

Physical

  • density · kg/m³2700
  • Mohs hardness6.5
source: Wikipedia

Sustainability

  • recyclabilityhigh as crushed aggregate; polished slab is reusable
  • biodegradableFalse
  • certificationsANSI/NSC 373
visual
speckled at any scale — pink-feldspar-on-gray is the cliché, but every quarry is its own picture
tactile
cold, dense, glassy under polish
weight perception
very heavy
acoustic
bright knock — denser than limestone; a tuning-fork analogue at slab scale

PBR starter values

finish · granular — open for table, JSON, host snippets, downloads

Principled BSDF defaults derived from the sphere granular finish. Reasonable seed for Blender, Substance, Keyshot, Rhino — tune per material. Or grab the whole library at once: ForMaterials library →

# finish:                   granular
albedo                      #988a90
metallic                    0.00
roughness                   0.85
ior                         1.45
transmission                0.00
clearcoat                   0.00
sheen                       0.00
anisotropic                 0.00
copy as JSON 
{
  "albedo": "#988a90",
  "metallic": 0.0,
  "roughness": 0.85,
  "ior": 1.45,
  "transmission": 0.0,
  "clearcoat": 0.0,
  "sheen": 0.0,
  "anisotropic": 0.0
}
Blender 4.x Python 
# Blender 4.x — Principled BSDF
# Granite · finish: granular
import bpy
mat = bpy.data.materials.new(name="mat_granite")
mat.use_nodes = True
bsdf = mat.node_tree.nodes["Principled BSDF"]
bsdf.inputs["Base Color"].default_value         = (0.314, 0.2542, 0.2789, 1.0)
bsdf.inputs["Metallic"].default_value           = 0.000
bsdf.inputs["Roughness"].default_value          = 0.850
bsdf.inputs["IOR"].default_value                = 1.450
bsdf.inputs["Transmission Weight"].default_value = 0.000
bsdf.inputs["Coat Weight"].default_value        = 0.000
bsdf.inputs["Sheen Weight"].default_value       = 0.000
bsdf.inputs["Anisotropic"].default_value        = 0.000
KeyShot Python (lux) 
# KeyShot 11+ — lux Python API, Generic material
# Granite · finish: granular
# Run from Window → Scripting Console
import lux
mat = lux.createMaterial(name="mat_granite", materialType="Generic")
mat.setProperty("diffuse",      (152, 138, 144))   # 8-bit sRGB
mat.setProperty("metallic",     0.000)
mat.setProperty("roughness",    0.850)
mat.setProperty("indexOfRefraction", 1.450)
mat.setProperty("transparency", 0.000)
mat.setProperty("coatingWeight", 0.000)
Substance pbrMetalRough 
{
  "_format": "Substance Designer / Painter \u2014 pbrMetalRough constants",
  "_about": "Granite \u00b7 finish: granular",
  "baseColor": {
    "r": 0.314,
    "g": 0.2542,
    "b": 0.2789
  },
  "metallic": 0.0,
  "roughness": 0.85,
  "ior": 1.45,
  "opacity": 1.0,
  "anisotropyLevel": 0.0,
  "_notes": "Channels listed are the standard Substance pbrMetalRough output. Drop into a Uniform Color node per channel, or as the constant input on a layered stack."
}
glTF 2.0 Metallic-Roughness 
{
  "asset": {
    "version": "2.0",
    "generator": "ForMatter"
  },
  "materials": [
    {
      "name": "mat_granite",
      "pbrMetallicRoughness": {
        "baseColorFactor": [
          0.314,
          0.2542,
          0.2789,
          1.0
        ],
        "metallicFactor": 0.0,
        "roughnessFactor": 0.85
      },
      "extensions": {
        "KHR_materials_ior": {
          "ior": 1.45
        }
      }
    }
  ]
}
USD Preview Surface 
# USD Preview Surface — UsdShade.MaterialLook prim attributes
# Granite · finish: granular
def Material "mat_granite" {
    token outputs:surface.connect = </mat_granite/PreviewSurface.outputs:surface>

    def Shader "PreviewSurface" {
        uniform token info:id = "UsdPreviewSurface"
        color3f inputs:diffuseColor = (0.314, 0.2542, 0.2789)
        float   inputs:metallic     = 0.000
        float   inputs:roughness    = 0.850
        float   inputs:ior          = 1.450
        float   inputs:opacity      = 1.000
        float   inputs:clearcoat    = 0.000
        token   outputs:surface
    }
}
↓ download glTF material
ProcessStone Carving (Hand and Pneumatic) · Water-Jet Cutting
Used inArchitectural Facade Panel
Substitutes
Limestone
Finishes that suit this material
Flamed stone finish · textured
Honed stone finish · matte
Leathered stone finish · textured
Polished stone finish · mirror

Second life

repairabilitymoderate — granite accepts honing-and-polishing restoration; cracks fill with epoxy.
recyclabilityhigh — crushed granite is high-value aggregate.
disposal pathaggregate market; concrete recycler.
typical longevity2000 years (typical)
failure modes
  • acid-etching from spilled wine / lemon (less severe than marble due to silica content but still possible)
  • thermal-shock cracking at large temperature gradients
  • staining from oil / pigment penetration in unsealed slabs

ICOMOS-ISCS stone-deterioration glossary; Marble Institute of America (MIA) granite care-and-cleaning guide.

Citations