Highlighting Hair...?

I have blonde hair- I am not much for dying my hair, but I've tried to highlight it a few times and some parts of it turn DARK BLACK immediately after I apply the bleaching solution to the strands (using a highlight kit) - why is this?Highlighting Hair...?
It may be that you have metal deposits on your hair. Metal will react with the lightener causing rapid oxidation and it will turn colors. Try this experiment:


1) take a snippet of your hair (take a big enough piece that you can see it, but not so big of a piece that you will have to change your style. Cut it from the back underneath part if possible.) Place this snippet of hair onto a piece of regular aluminum foil. Tape one end of it to the foil so it will stay in tact. Apply the lightening solution to it... watch what happens... does it actually turn the hair black, or just the product turns black? If just the product turns black and the hair lightens to the desired color and stays like hair (not mush) then you will be fine. It's better to see what will happen on a small piece of hair then over your whole head.


2) Try doing a clarifying treatment. Get a good clarifying shampoo.. shampoo your hair once with it, rinse well. Then shampoo again this time leave the shampoo in the hair for a good 10 minutes. Rinse well. Then take another snippet of hair and repeat the experiment again and see if that makes a difference. The clarifying treatment should remove enough metal deposits to make the undesired color change nonexistent, or reduced anyway.Highlighting Hair...?
It just happens. It probably has something to do with the color mixing with oxygen or something. If you leave the solution in the bottle for a long time all of the solution will turn that color. Just as long as your hair turns out the right color you're fine.