John Holland (August 25, 1838 – 1917) was an American businessman and industrialist whose eponymous company, John Holland Gold Pen Company, was a large maker of pens and related products during the late 19th century.
In his business activities, he made several metallurgical and mechanical advancements, the most notable being a process for creating stable bars and other usable forms of iridium.
[1] He was born on August 25, 1838, in Kilcrohane, County Cork, Ireland, and emigrated, with his parents, to the United States in 1848.
In 1880, Holland discovered the ability to melt and make castings of iridium by fusing the white-hot ore with phosphorus,[1] and patented the process in the United States.
[3] He invoked the help of William Lofland Dudley in getting rid of the phosphorus, who did so by repeated applications of lime at great heat.