12 Uses of Dragon Blood
I'm re-reading the series and there's been mention three times just in the first book that Dumbledore discovered the 12 uses of dragon's blood, but so far, nothing on what those uses might actually be. In my head, I know that it isn't particularly important to the overall story, but there's a tiny voice (that sounds suspiciously like Emma Watson) that keeps squeaking 'what are the 12 uses of dragon's blood?!' I looked on the Lexicon, and they only mention the 12th one, oven cleaning. Anyone know what the other 11 are?