Bayer had been working in Saint Petersburg to develop a method to provide alumina to the textile industry, which used it as a fixing agent in the dyeing of cotton. In 1887, he discovered that aluminium hydroxide precipitated from an alkaline solution which is crystalline and can be filtered and washed more easily than that precipitated from an acid medium by neutralization. In 1888, Bayer developed and patented his four-stage Bayer process of extracting alumina from bauxite ore.
The 1855 Paris Exhibition exhibited a bar of aluminum alongside the Crown Jewels. Along with the Hall-Héroult process, Bayer's solution caused the price of aluminum to drop about 80% in 1890 from what it had been in 1854.
United States Patent Application 20050238571: Process and apparatus for the production of alumina