From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Comparative data table for the properties of H.C. Copper and Aluminium.
| Identifier | ExFiles\Box 168\1\ img138 | |
| Date | 8th January 1934 | |
| Messrs. Rolls Royce Ltd. 8th January, 1934 Comparative Data for H.C. Copper and Aluminium Copper Aluminium Conductivity (electrical) 100 61.5 Tensile strength (Unannealed) 25 - 30 tons 12 - 15 tons Melting Point 1200°C 700°C Specific Gravity 8.9 2.7 Section for Equal Conductivity 1 1.66 Diameter 1 1.28 Weight 1 .495 Temperature co-efficient per degree centigrade .00428 .0032 | ||