Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 146,754 pages of information and 232,400 images on early companies, their products and the people who designed and built them.
of Continental and of Novo Steel Works, Sheffield
1878 Advertising their tool steel, drill rod, and 'Continental' needle wire, etc in the USA. Agents for USA and Canada: M. Diamond & Co. US Warehouse: 8 Ford Street, Hartford, Conn.
1892 Incorporated as a private limited company.
1903 Mr B. Hunstman wrote to The Times pointing out that Ajax steels from his company and steels from Messrs Jonas and Colver, probably the largest producer of high speed steels, were of comparable quality to those of Armstrong Whitworth for tool making.
1907 Re-registered as a private limited company. Presumably at this time was renamed Sir Joseph Jonas, Colver & Co., Ltd.
1914 Steel manufacturers. Specialities; crucible cast steel of every description; "Novo Superior" and "Novo" best special high-speed steels; Siemens-Martin steel, cold rolled steel and wire; files, hammers, saws and mining and quarry tools. Employees 2,500. 
Renamed Jonas and Colver
1937 Steel and file manufacturers. 
1967 One of the larger makers of high speed and tool steels not subject to nationalisation
1974 Designed a new carbide face milling cutter which removed large amounts of metal using a new tool geometry.