Mineralogist, crystallographer, lecturer, collector and research scientist, Gordon spent most of his active life as a member of the staff of the Academy of Natural Sciences, leaving only to join the country's research effort during the Second World War. The correspondence preserved here dates mostly from 1943-49. The subjects covered are almost entirely of a mineralogical nature, but often deal with the problems of exhibits, collecting, the local mineralogical society, and identifications for friends and amateurs. Letters are preserved from 86 persons, with a total of 193. Gordon's answers and queries have been estimated as another 200.