Blessing to all of you.
I feel that we forget that black salt is very helpful in spell work. For example I used it today to soak up negative energy that may come my way. I put a fine line across the door of the people who can virtually send negative vibes and wrongful information towards me and cause me to be written up.
The color black soaks in all sort of energy. But it attracts negative energy as a magnet and keeps hold of it. So I guess you can use this for dark magic as well. I have not had to use it in that way, but it should give it a boost.
White reflects and black soaks in. So if you use black salt in a spell let me know how it worked out for you.
Sweet blessings to you all.