Blessing to you all.
We all know the power of color. Now black is a very strong color it is often used as a protective color. Some see you wear black and automatically think your depressed. If you wear a hint of black that is more than enough for protection. I will wear a black choker that I made or I will carry an onyx stone in my pocket. It does the trick because I have not had so many problems. It’s almost like warding off the evil eye.
White also a very strong color. Used for protection and at time cleansing. I visualize a bright white light surrounding me when I am doing an aura cleansing. It is also a comforting light. I think because it not only protects but once it clears your aura you do feel like your being hugged by the light.
Both are powerful enough for spell work but make sure of the nature. People usually associates black for dark magic. It does not necessarily have to be that way. You can use black for positive spells and white for negative spells.
My advice study your colors and the power they emits. It will definitely help in spell work.