These IOR values are taken from the great resource RefractiveIndex.INFO, but it only includes the values relevant for setting up materials for physically based rendering.
The values listed here should work with several different rendering engines, such as Octane Render and Arnold.
| Red (650nm) | Green (550nm) | Blue (450nm) | ||
|---|---|---|---|---|
| Aluminium (Al) | n= | 1.34560 | 0.96521 | 0.61722 |
| k= | 7.47460 | 6.39950 | 5.30310 | |
| Brass (Cu-Zn) | n= | 0.44400 | 0.52700 | 1.09400 |
| k= | 3.69500 | 2.76500 | 1.82900 | |
| Copper (Cu) | n= | 0.27105 | 0.67693 | 1.31640 |
| k= | 3.60920 | 2.62480 | 2.29210 | |
| Gold (Au) | n= | 0.18299 | 0.42108 | 1.37340 |
| k= | 3.42420 | 2.34590 | 1.77040 | |
| Iron (Fe) | n= | 2.91140 | 2.94970 | 2.58450 |
| k= | 3.08930 | 2.93180 | 2.76700 | |
| Lead (Pb) | n= | 1.91000 | 1.83000 | 1.44000 |
| k= | 3.51000 | 3.40000 | 3.18000 | |
| Mercury (Hg) | n= | 2.07330 | 1.55230 | 1.06060 |
| k= | 5.33830 | 4.65100 | 3.86280 | |
| Platinum (Pt) | n= | 2.37570 | 2.08470 | 1.84530 |
| k= | 4.26550 | 3.71530 | 3.13650 | |
| Silver (Ag) | n= | 0.15943 | 0.14512 | 0.13547 |
| k= | 3.92910 | 3.19000 | 2.38080 | |
| Titanium (Ti) | n= | 2.74070 | 2.54180 | 2.26700 |
| k= | 3.81430 | 3.43450 | 3.03850 |
More metals (and formats)
The values listed above are only the materials found in the 3D section of RefractiveIndex.INFO, but I also collected the appropriate values for some other metals, that could be interesting, from the database. You can find them (and the values listed above) in this Google Document Spreadsheet.
(I leave no guarantee on the accuracy on the values, but I have tested them all).
Octane Materials
If you use Octane in Blender you can download this .blend (zipped) with a material for each metal (21) setup with the correct values (the .blend includes both a material and a node group for each metal).
If you use Octane Standalone, or in another software, I’ve also provided a set of .ORBX
NB: These are not fully setup materials, just “stubs” (Universal Material w/ Metal – RGB IOR), just so you don’t need to find and enter all the values each time.
(Files update 25-03-25 for newer versions of Octane Blender, and added Stainless Steel)
Cycles/Eevee materials
Since I first collected this information, and set up the Blender Octane Materials, a physically based shader (Metallic BSDF) has been added to Cycles/Eevee. So now I’ve set up Cycles shaders for each metal (21), in the same way as for Octane Blender: A material for each metal, as well as a node group. With the slight difference that the node groups exposes the Roughness and Normal.
NB: These are not fully setup materials, just “stubs” (Metallic BSDF – Physical Conductor), just so you don’t need to find and enter all the values each time.
| Metals_IOR_Cycles.blend (7z) / Google Drive |
| Metals_IOR_Cycles.blend (zip) / Google Drive |
| Metals_IOR_Cycles.blend / Google Drive |
Previews/Examples
If you want to know how these materials (might) look (and compare), take a look at these galleries:
Public Domain
This is provided free of charge and no ownership or copyright is claimed (in the same way as the data provided by RefractiveIndex.info).
Released as Public Domain / CC-0