 Many of the alternate sources sold similar looking color products with unreliable staining.Prof J. E. Scott worked to decipher the chemistry of Alcian blue, which was known only to the Industry but kept as a tight trade secret.After spending 3 man-years of effort in 1972 he published the structure of Alcian blue and was able to get ICI to confirm it in 1973, incidentally in the same time that ICI also had just stopped producing it.