Available bulk resistivity values (ρ) and relative permeability (μr)used to calculate skin depths (δσ) can vary considerably depending on the source. In fact, the values for permeabilities are so far-ranging that I hesitated to even include any of them in the table. The ones used here are typical, gathered from many of the links listed at the bottom of the page. Therefore, it is incumbent upon the user to determine his own value based on a trusted source. Even NIST1 and CRC2 do not fully agree on bulk resistivity values for materials as well-known as copper and aluminum. Most common conductors used in cabling have a relative permeability of very near unity (1).
(click here for the equation for skin depth)
(click here for a skin depth calculator)
| Material | Chemical
Formula | Bulk
Resistivity
@20C
µΩ×cm
(Ω×10-8m) | Relative Permeability μ/μ0 | Skin Depth
(µm@f) | 1
MHz | 10
MHz | 100
MHz | 1
GHz | 10
GHz | 100
GHz |  | | Aluminum | Al | 2.65 | 1 | 81.9 | 25.9 | 8.19 | 2.59 | 0.819 | 0.259 | | Beryllium | Be | 3.3 | 1 | 91.4 | 28.9 | 9.14 | 2.89 | 0.914 | 0.289 | | Brass | Cu70/Zn30 | 7 | 1 | 133 | 42.1 | 13.3 | 4.21 | 1.33 | 0.421 | | Bronze | Cu89/Sn11 | 15 | 1 | 195 | 61.6 | 19.5 | 6.16 | 1.95 | 0.616 | | Carbon | C (graphite) | 1375 | | 1866 | 590 | 187 | 59.0 | 18.7 | 5.90 | | Cadmium | Cd | 7.3 | | 136 | 43.0 | 13.6 | 4.30 | 1.36 | 0.430 | | Chromium | Cr | 13.2 | 1 | 183 | 57.8 | 18.3 | 5.78 | 1.83 | 0.578 | | Cobalt | Co | 6.34 | 600 | 5.8 | 1.6 | 0.52 | 0.16 | 0.052 | 0.016 | | Constantan | Cu60Ni40 | 49 | | 352 | 111 | 35.2 | 11.1 | 3.52 | 1.11 | | Copper | Cu | 1.69 | 1 | 65.4 | 20.7 | 6.54 | 2.07 | 0.654 | 0.207 | | Dural | Al95/Cu 4/Mg 1 | 5 | | 112.54 | 35.6 | 11.3 | 3.56 | 1.13 | 0.356 | | Gallium | Ga | 15.5 | | 198 | 62.7 | 19.8 | 6.27 | 1.98 | 0.627 | | Gold | Au | 2.2 | 1 | 74.7 | 23.6 | 7.47 | 2.36 | 0.747 | 0.236 | | Graphite | C | 783.7 | | 1409 | 446 | 141 | 44.6 | 14.1 | 4.46 | | Inconel alloy 600 | Ni72/Cr16/Fe 8 | 103 | 1 | 511 | 162 | 51.1 | 16.2 | 5.11 | 1.62 | | Indium | In | 8.8 | | 149 | 47.2 | 14.9 | 4.72 | 1.49 | 0.472 | | Iridium | Ir | 5.1 | | 114 | 35.9 | 11.4 | 3.59 | 1.14 | 0.359 | | Iron | Fe | 10.1 | 500 | 7.2 | 2.3 | 0.72 | 0.23 | 0.072 | 0.023 | | Lead | Pb | 20.6 | 1 | 228 | 72.2 | 22.8 | 7.22 | 2.28 | 0.722 | | Lithium | Li | 9.29 | | 153 | 48.5 | 15.3 | 4.85 | 1.53 | 0.485 | | Magnesium | Mg | 4.2 | 1 | 103 | 32.6 | 10.3 | 3.26 | 1.03 | 0.326 | | Mercury | Hg | 95.9 | 1 | 493 | 156 | 49.3 | 15.6 | 4.93 | 1.56 | | Molybdenum | Mo | 5.7 | 1 | 120 | 38.0 | 12.0 | 3.80 | 1.20 | 0.380 | | Monel alloy 400 | Ni65/Cu33/Fe 2 | 49 | | 352 | 111 | 35.2 | 11.1 | 3.52 | 1.11 | | mu-Metal | | 47 | 30,000 | 2.0 | 0.64 | 0.20 | 0.064 | 0.020 | 0.0064 | | Nickel | Ni | 6.9 | 200 | 9.3 | 3.0 | .093 | 0.30 | 0.093 | 0.030 | | Nichrome | Ni80/Cr20 | 108 | | 523 | 165 | 52.3 | 16.5 | 5.23 | 1.65 | | Palladium | Pd | 10.8 | 1 | 165 | 52.3 | 16.5 | 5.23 | 1.65 | 0.523 | | Platinum | Pt | 10.58 | 1 | 164 | 51.8 | 16.4 | 5.18 | 1.64 | 0.518 | | Potassium | K | 6.8 | | 131 | 41.5 | 13.1 | 4.15 | 1.31 | 0.415 | | Rhodium | Rh | 4.7 | 1 | 109 | 34.5 | 10.9 | 3.45 | 1.09 | 0.345 | | Silver | Ag | 1.63 | 1 | 64.3 | 20.3 | 6.43 | 2.03 | 0.643 | 0.203 | | Sodium | Na | 4.9 | | 111 | 35.2 | 11.1 | 3.52 | 1.11 | 0.352 | | Steel | | | 100 | | | | | | | | Tantalum | Ta | 13.5 | | 185 | 58.5 | 18.5 | 5.85 | 1.85 | 0.585 | | Tantalum Nitride | TaN | 252 | | 799 | 253 | 79.9 | 25.3 | 7.99 | 2.53 | | Tin (pure) | Sn | 12.6 | 1 | 179 | 56.5 | 17.9 | 5.65 | 1.79 | 0.565 | | Titanium | Ti | 54 | 1 | 370 | 117 | 37.0 | 11.7 | 3.70 | 1.17 | | Tungsten | W | 5.4 | 1 | 117 | 37.0 | 11.7 | 3.70 | 1.17 | 0.370 | | Urnaium | U | 27 | | 262 | 82.7 | 26.2 | 8.27 | 2.62 | 0.827 | | Yttrium | Y | 53 | | 366 | 116 | 36.6 | 11.6 | 3.66 | 1.16 | | Zinc | Zn | 5.96 | | 123 | 38.9 | 12.3 | 3.89 | 1.23 | 0.389 | | Zirconium | Zr | 44 | | 334 | 106 | 33.4 | 10.6 | 3.34 | 1.06 |
1: National Institute of Standards and Technology
2: Chemical Rubber Corporation
HyperPhysics Reference hyperphysics.phy-astr.gsu.edu/hbase/Tables/rstiv.html Institute of Science Technology www.istonline.org.uk/Handbook.htm Hamilton Precision Metals http://www.hpmetals.com/metals.php IMI Scott Ltd www.imiscott.co.uk/reswire_table.html H Cross Company hcrosscompany.com/metals/metals.htm WebElements Periodic Table www.webelements.com The Cemtach Group http://www.cemtach.com/cgi-bin/emMaterialSearch.cgi?order_by=mur&order=321&page=2
| 
Kirt
