Re: Blue Black/Jet Black! What\'s the difference
Whether or not your hair turns green when you use blue black has to do with whether the base colors are just green or blue, or they have something added to them (a neutral or violet base). It also has to do with youur base color. If it's just blue-green and your base color is light enough and has a gold undertone, you can end up green.
If your natural undertones are very red, that alone may be enough to counter a pure green or blue base. If a stylist added something to your hair before the color it's either a toner (which reguulates the tonality of the finished result) or a version of a red color to counteract the green.
Rule of thumb - blue black on hair with a gold base - whether true gold or golden brown - will go green. Blue black on red hair will not. Mixed base blacks (like jet black) will not. If you have a gold natural base, you can still use a blue black if you mix it with a red in the same formula. The ratio is about 3 parts blue-black, to 1 part red.