Charles Frederick Osborne, civil engineer, was employed in the Public Works Department of the Cape Colony and stationed at the goldfields around Knysna during the eighteen-seventies. He compiled a map of the road between George and Knysna in 1875 and the next year a map of the goldfields at Ruigtevlei, west of Knysna, showing the position of the mine shaft, the conglomerates, and the Karatara River. That same year an article by him, "Gold at Knysna" was published in the Cape Monthly Magazine (Series 2, 1876, Vol. 12, pp. 123-125 and 256). The article consisted of a letter to the editor and a report addressed to the chief inspector of public works.
Osborne was subsequently transferred to Port Nolloth as resident engineer, from where he applied for an appointment at the harbour works in Durban. He was in Natal by 1879, in charge of the wharves and works at the Point in Durban, but became involved in a dispute with the authorities and with the colonial engineer, Albert H. Hime. In 1884 he reported his discovery of gold on the farm Gorton, neat Ixopo. That same year he wrote a monograph, South African goldfields, and machinery to work them (Pietermaritzburg, 1884, 47 pp). He was declared insolvent the next year.
After E.J. Dunn* had reported favourably on the Millwood goldfields near Knysna, Osborne assisted Thomas C.J. Bain*, who had been appointed acting mining commissioner there, to investigate the finds. Bains's Report on the recent gold discoveries in the Knysna Division (Parliamentary Report G46-86, May 1886, 8 pp) presented a positive assessment of the finds. Osborne contributed a description of the goldfields, with a map (scale 1:3600) and section. In 1887 he was again declared insolvent and a legal case was initiated against him by the directors of the Millwood Gold Mining and Prospecting Company, Ltd. Some years later he wrote a more comprehensive description of the Millwood goldfields for the Wynberg Times. His account was reprinted in the form of a monograph, The Knysna-Millwood gold-fields (Wynberg, 1890, 41 pp).
In 1895, the year of his death, Osborn and A.A. Nobel were trading in the South African Republic (Transvaal) under the name C.F. Osborne and Co.