Guillaume Delprat was born in Delft in the Netherlands in 1856, and from the age of 17 served an engineering apprenticeship in Scotland while studying science and physics.
He commenced his mining career in Spain, finding and reworking silver mines dating from Roman times. He later worked in Mexico and North America, and as a consultant based in London.
In 1898, he accepted an offer to become the Assistant General Manager of the Broken Hill Proprietary Co Ltd’s (BHP) Broken Hill operation, and was appointed General Manager the year after. He developed the Potter-Delprat flotation process in conjunction with Charles Potter in the early 1900s. Delprat was responsible for BHP’s adoption of flotation and the associated change in emphasis to zinc production, moving the lead smelters to Port Pirie and establishing the Newcastle steelworks for which he was awarded a CBE in 1918.
However, Delprat was criticised for his role in a major industrial dispute at Broken Hill in 1908-09. He was an active council member and president of the AusIMM in 1906, being awarded the first Institute Medal in 1935 in recognition of eminent services in the advancement of mining and metallurgical science and practice, and particularly in regard to his work at Broken Hill and establishing the steelworks in Newcastle.