ForMatter/Materials/gemstone/Moissanite (Synthetic)
mat_gem_simulant_moissanite

Moissanite (Synthetic)

silicon carbide (SiC, hexagonal 6H polytype), diamond simulant · moissanite, silicon carbide gem, synthetic SiC
highlast updated 2026-04-27
metallic 0.00
hue shift +0°

Silicon carbide grown into gem-quality single crystals — harder than CZ, more brilliant than CZ, and more diamond-like in optical character. Originally found in tiny natural quantities in a meteor crater (Henri Moissan, 1893, Canyon Diablo) and now grown commercially since 1998 by Charles & Colvard. The most plausible diamond alternative for the unaided eye — distinguishable from diamond by its higher dispersion (which reads as "too rainbow") and its double-refraction.

α-SiC (6H polytype dominant), hexagonal crystal system. Mohs ~9.25 (GIA gemological convention) to 9.5 (general mineralogical) — harder than CZ, only diamond and a few rare gems exceed. Specific gravity 3.21 (close to diamond's 3.52). Refractive indices nₒ 2.654 / nₑ 2.691 (positive uniaxial, ne > no) — birefringent, a double image visible through facets under loupe. Dispersion 0.104 (more than double diamond's). Thermal conductivity high enough that older diamond-tester probes give false-positive — moissanite-specific testers became standard in the trade post-1999.

mechanical

  • mohs_hardness_range9.25 (GIA) to 9.5 (general mineralogical)
  • knoop_hardness_kg_mm22900
  • specific_gravity3.21
source: GIA Moissanite Quality Factors; Hurlbut & Klein, *Manual of Mineralogy*

optical

  • refractive_index_no_ordinary2.654
  • refractive_index_ne_extraordinary2.691
  • dispersion0.104
  • birefringence0.037
  • _notepositive uniaxial — ne > no
source: GIA; Hurlbut & Klein, *Manual of Mineralogy*

Sustainability

  • embodied carbon kg co2e per kg32
  • sourceEditorial estimate from ICE / Granta CES EduPack class databases — industry mean, with cradle-to-gate boundary unless otherwise noted. Embodied carbon for any specific product depends on supplier mix, recycled content, and energy grid; verify against a primary source before using these numbers in a sustainability claim.
  • recyclabilitymoderate
  • biodegradableFalse
  • localityprimary production: USA (Charles & Colvard / Cree-Wolfspeed)
visual
very bright with characteristically "rainbow" dispersion that reads slightly louder than diamond
tactile
indistinguishable from diamond by hand

PBR starter values

Principled BSDF defaults derived from the sphere crystalline finish. Reasonable seed for Blender, Substance, Keyshot, Rhino — tune per material.

# finish:      crystalline
albedo        #f0f8f0
metallic      0.00
roughness     0.05
ior           2.42
transmission  1.00
clearcoat     0.00
sheen         0.00
anisotropic   0.00
copy as JSON 
{
  "albedo": "#f0f8f0",
  "metallic": 0.0,
  "roughness": 0.05,
  "ior": 2.42,
  "transmission": 1.0,
  "clearcoat": 0.0,
  "sheen": 0.0,
  "anisotropic": 0.0
}
Blender 4.x Python 
# Blender 4.x — Principled BSDF
# Moissanite (Synthetic) · finish: crystalline
import bpy
mat = bpy.data.materials.new(name="mat_gem_simulant_moissanite")
mat.use_nodes = True
bsdf = mat.node_tree.nodes["Principled BSDF"]
bsdf.inputs["Base Color"].default_value         = (0.8714, 0.9387, 0.8714, 1.0)
bsdf.inputs["Metallic"].default_value           = 0.000
bsdf.inputs["Roughness"].default_value          = 0.050
bsdf.inputs["IOR"].default_value                = 2.420
bsdf.inputs["Transmission Weight"].default_value = 1.000
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
# Moissanite (Synthetic) · finish: crystalline
# Run from Window → Scripting Console
import lux
mat = lux.createMaterial(name="mat_gem_simulant_moissanite", materialType="Generic")
mat.setProperty("diffuse",      (240, 248, 240))   # 8-bit sRGB
mat.setProperty("metallic",     0.000)
mat.setProperty("roughness",    0.050)
mat.setProperty("indexOfRefraction", 2.420)
mat.setProperty("transparency", 1.000)
mat.setProperty("coatingWeight", 0.000)
Substance pbrMetalRough 
{
  "_format": "Substance Designer / Painter \u2014 pbrMetalRough constants",
  "_about": "Moissanite (Synthetic) \u00b7 finish: crystalline",
  "baseColor": {
    "r": 0.8714,
    "g": 0.9387,
    "b": 0.8714
  },
  "metallic": 0.0,
  "roughness": 0.05,
  "ior": 2.42,
  "opacity": 0.0,
  "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_gem_simulant_moissanite",
      "pbrMetallicRoughness": {
        "baseColorFactor": [
          0.8714,
          0.9387,
          0.8714,
          1.0
        ],
        "metallicFactor": 0.0,
        "roughnessFactor": 0.05
      },
      "extensions": {
        "KHR_materials_ior": {
          "ior": 2.42
        },
        "KHR_materials_transmission": {
          "transmissionFactor": 1.0
        }
      }
    }
  ]
}
USD Preview Surface 
# USD Preview Surface — UsdShade.MaterialLook prim attributes
# Moissanite (Synthetic) · finish: crystalline
def Material "mat_gem_simulant_moissanite" {
    token outputs:surface.connect = </mat_gem_simulant_moissanite/PreviewSurface.outputs:surface>

    def Shader "PreviewSurface" {
        uniform token info:id = "UsdPreviewSurface"
        color3f inputs:diffuseColor = (0.8714, 0.9387, 0.8714)
        float   inputs:metallic     = 0.000
        float   inputs:roughness    = 0.050
        float   inputs:ior          = 2.420
        float   inputs:opacity      = 0.000
        float   inputs:clearcoat    = 0.000
        token   outputs:surface
    }
}
↓ download glTF material
Substitutes
Cubic Zirconia (CZ)
Lab-Grown Diamond (CVD)
Natural Diamond

Citations