banjo - I looked up your question because I was curious. It was interesting to read the list of 'rules'. They accept gray, dyed, and permed hair but not bleached hair. They sell the gray hair and use the money for their regular expenses.
knotty - Gray hair is very individual. Some people have gray hair that is just like their other hair. Some comes in kinkier or curlier or straighter or coarser or finer.