William Aspdin

William Aspdin (23 September 1815 – 11 April 1864) was an English cement manufacturer, and a pioneer of the Portland cement industry. He is considered the inventor of "modern" Portland cement. In 1824, Joseph obtained a patent for Portland cement, a relatively fast-setting cement usable only in mortars and stuccos.

William joined his father's cement manufacturing firm in 1829, at the age of fourteen. In July 1841, Aspdin left the firm after a major disagreement with his father. Joseph then went into partnership with his elder son, James, posting a notice that Aspdin had left, and that the company would not be responsible for his debts, stating "I think it right to give notice that my late agent, William Aspdin, is not now in my employment, and that he is not authorised to receive any money, nor contract any debts on my behalf or on behalf of the new firm."

In 1843, Aspdin set up a manufacturing plant at Rotherhithe, southeast London, where he was soon making a cement that caused a sensation among users in London. William had discovered that a significantly different product, with much wider applications, could be made by modifying his father's cement formulation. By increasing the limestone content in the mixture, and burning it much hotter, a slow-setting, high-strength product suitable for use in concrete could be obtained. This product was substantially more expensive to make, in terms of cost of extra limestone, cost of extra fuel, and difficult grinding of the hard clinker.

Aspdin contracted several partnerships to finance his operations. As "Maude, Jones & Aspdin", he acquired the Parker and Wyatt plant at Northfleet Creek in Kent, and transferred his manufacturing operations there in 1846. He sold out his share of the Northfleet plant in 1852, and set up in Gateshead, County Durham, as "Aspdin, Ord & Co". In 1857, he sold out again, and moved to Germany. From 1860, he set up cement plants at Altona and Lagerdorf, these being the first plants to make modern Portland cement outside the UK. He died at Itzehoe near Hamburg on 11 April 1864. He is credited with launching the "modern" Portland cement industry.