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).
Letter from Johnson Matthey & Co. Limited detailing the composition of 'Post Office Metal' alloys.
| Identifier | ExFiles\Box 50\2\ Scan198 | |
| Date | 22th October 1927 | |
| X 4335 JOHNSON MATTHEY & CO. LIMITED 73/83, HATTON GARDEN, LONDON, E.C.1. 22nd. October 1927. ROY {Sir Henry Royce} 6/MG21.10.27. E {Mr Elliott - Chief Engineer} /JC/IA. Messrs. Rolls-Royce Ltd., Derby. Dear Sirs, Replying to your favour of the 21st inst. on the subject of "Post Office Metal", we would advise you that there are two Post Office Alloys, one 10% Gold, 90% silver, and the other, 67% gold, 26% silver and 7% platinu, If you will kindly let us know the size of the contacts required, we shall be pleased to make you a few samples for testing purposes. With compliments, We are, dear Sirs, Yours faithfully, | ||