Ooh! How interesting...I haven't tried it on my hair but I mixed some in a face mask with another clay powder (fuller's earth) and got really glowy skin. I will give this a try! Is it something to do with the silica content do you think?
(I have also taken it internally and didn't experience any problems but I haven't done this for a while).
ETA: I notice your formula had a lot of other hair-beneficial herbs and ingredients so they would have contributed to the effects as well I suppose. Do you think the DE just helped with the consistency of the mixture...?
I may try being a guinea pig and doing a more simple DE hair mask....maybe adding oil or aloe if I feel it needs it to help the consistency.
I'll report back :-)