Its most important patent was the discovery that a small percentage of oil, agitated into a froth, was needed to make the process commercially successful at Broken Hill.
835,120, issued on November 6, 1906, to Henry Livingston Sulman, Hugh Fitzalis Kirkpatrick-Picard (the two prominent consultant metallurgists and directors of the firm) and John Ballot.
And in 1923, Minerals Separation staff chemists in the San Francisco office, Cornelius Keller and Carl Lewis under director Edward H. Nutter, perfected the use of chemical xanthates, replacing the use of oil and easing the workings in the froth cells.
[2] Because of the many claims of primacy, the Minerals Separation Lt history is one of constant litigation over its patents, with the British House of Lords and the U. S. Supreme Court (twice) deciding in its favor.
In 1911, the company opened an office in San Francisco under Edward Nutter, which eventually incorporated as the Minerals Separation North American Corporation.