Other drafts included a character by the name of 'Pyrites', whose name means 'fool's gold'. He was a servant of Voldemort's and was meeting Sirius in front of the Potters' house. Pyrites, too, had to be discarded, though I quite liked him as a character; he was a dandy and wore white silk gloves, which I thought I might stain artistically with blood from time to time.
-- J.K. Rowling in "Extra Stuff" on her Official Site (JKR)
Argus Pyrites was servant of Voldemort, quite a dandy wearing white silk gloves.
This character is not canon because he was edited out of the books, but in a very early version of Book 1 he is mentioned as the author of Alchemy, Ancient Art and Science (JKR scrapbook extra).