ForMatter/Materials/metal/Sterling Silver (925)
mat_silver_sterling_925

Sterling Silver (925)

precious metal alloy, copper-strengthened silver · sterling, .925 silver, Ag 92.5 Cu 7.5, standard silver
metallic 0.00
hue shift +0°

What "silver" almost always means in a jewelry case — 92.5% Ag, 7.5% Cu. The copper isn't there to cheapen it, it's there to make it usable: pure silver bends in your hand, sterling holds a ring shape and a knife edge. The trade is fire-scale and tarnish, both legacies of that copper. Sterling is the standard the standard is named after — every other silver alloy on this page is positioned against it.

Ag 92.5 / Cu 7.5 nominal per the British/American sterling standard. Two-phase microstructure (Ag-rich solid solution + Cu-rich eutectic) responds to age-hardening; precipitation hardening at 280–300 °C raises Vickers hardness above 130 HV. Liquidus 893 °C, solidus 779 °C. Fire-scale (subsurface Cu₂O) forms during torch work in oxidizing atmospheres and must be either prevented (firecoat / boric flux) or removed (depletion gilding) before finishing.

mechanical

  • tensile_strength_mpa_annealed220
  • tensile_strength_mpa_hardened380
  • yield_strength_mpa_annealed110
  • elongation_pct_annealed35
  • hardness_vickers_annealed60
  • hardness_vickers_age_hardened135
  • density_kg_m310360
source: ASM Handbook Vol. 2; Untracht, *Jewelry Concepts and Technology*

thermal

  • liquidus_c893
  • solidus_c779
  • thermal_conductivity_w_mk360
source: CRC Handbook; Rio Grande technical bulletin

Sustainability

  • embodied carbon kg co2e per kg130
  • 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.
  • embodied carbon recycled kg co2e per kg28
  • recyclabilityvery high — refiner re-purifies to fine silver and re-alloys; bench scrap economically worth recovering
  • biodegradableFalse
  • certificationsRJC Code of Practices, Fairmined Silver (when sourced certified)
  • localityglobal; the alloying happens at refineries near jewelry-manufacturing centers (Italy, Thailand, USA)
visual
warmer-cast white than fine silver, mirror-bright polished, develops gray-to-black tarnish in patches around copper-rich grain boundaries
tactile
noticeably stiffer than fine silver, cool, takes a hand-rubbed finish that fine silver can't hold
weight perception
heavy
acoustic
clear high-pitched ring on a hard surface — the test for a fake silver coin

PBR starter values

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

# finish:      metallic
albedo        #c0c0c8
metallic      1.00
roughness     0.25
ior           1.45
transmission  0.00
clearcoat     0.00
sheen         0.00
anisotropic   0.00
copy as JSON
{
  "albedo": "#c0c0c8",
  "metallic": 1.0,
  "roughness": 0.25,
  "ior": 1.45,
  "transmission": 0.0,
  "clearcoat": 0.0,
  "sheen": 0.0,
  "anisotropic": 0.0
}
Blender 4.x Python
# Blender 4.x — Principled BSDF
# Sterling Silver (925) · finish: metallic
import bpy
mat = bpy.data.materials.new(name="mat_silver_sterling_925")
mat.use_nodes = True
bsdf = mat.node_tree.nodes["Principled BSDF"]
bsdf.inputs["Base Color"].default_value         = (0.5271, 0.5271, 0.5776, 1.0)
bsdf.inputs["Metallic"].default_value           = 1.000
bsdf.inputs["Roughness"].default_value          = 0.250
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
# Sterling Silver (925) · finish: metallic
# Run from Window → Scripting Console
import lux
mat = lux.createMaterial(name="mat_silver_sterling_925", materialType="Generic")
mat.setProperty("diffuse",      (192, 192, 200))   # 8-bit sRGB
mat.setProperty("metallic",     1.000)
mat.setProperty("roughness",    0.250)
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": "Sterling Silver (925) \u00b7 finish: metallic",
  "baseColor": {
    "r": 0.5271,
    "g": 0.5271,
    "b": 0.5776
  },
  "metallic": 1.0,
  "roughness": 0.25,
  "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_silver_sterling_925",
      "pbrMetallicRoughness": {
        "baseColorFactor": [
          0.5271,
          0.5271,
          0.5776,
          1.0
        ],
        "metallicFactor": 1.0,
        "roughnessFactor": 0.25
      },
      "extensions": {
        "KHR_materials_ior": {
          "ior": 1.45
        }
      }
    }
  ]
}
USD Preview Surface
# USD Preview Surface — UsdShade.MaterialLook prim attributes
# Sterling Silver (925) · finish: metallic
def Material "mat_silver_sterling_925" {
    token outputs:surface.connect = </mat_silver_sterling_925/PreviewSurface.outputs:surface>

    def Shader "PreviewSurface" {
        uniform token info:id = "UsdPreviewSurface"
        color3f inputs:diffuseColor = (0.5271, 0.5271, 0.5776)
        float   inputs:metallic     = 1.000
        float   inputs:roughness    = 0.250
        float   inputs:ior          = 1.450
        float   inputs:opacity      = 1.000
        float   inputs:clearcoat    = 0.000
        token   outputs:surface
    }
}
↓ download glTF material

Citations