A separate blending brush for each pack of eyeshadows?

Hi! More makeup questions for ya! I bought a few Maybelline quad eyeshadow packs, in different shades. I also bought one blending brush. So let's say I want to use the purple shadows one day, and I blend with the brush, then the next day I want to wear the brown shades. Do I have to wash the brush before using it with the browns? Or will it even matter? Or should I buy a separate brush for each pack? $$$ Thanks!A separate blending brush for each pack of eyeshadows?
You should wash your brush before using it with the browns because if you use a darker color with your shading brush and you don't wash it, then there will be still remains of that dark eyeshadow on the shading brush. If you were to use it again, but on a lighter color, then, the darker color would show, but blended with the light color. If you want to blend a specific color, then it may come out to a different color you didn't expect.A separate blending brush for each pack of eyeshadows?
Just spray a little brush cleaner on it and wipe it off on a towel.

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