I've recently started making bath salts with liquid lake dyes from TKB Trading - and I've noticed that certain color blends are fading pretty quickly. I made a purple blend (red 21, red 30 and blue 1) which fades when used with epsom and pacific salts - but the more concerning part is that when used with dead sea salts, it seems like the red and blue dyes separate as well. I'm also noticing this color separation with my lighter green blends.
These salts aren't exposed to sunlight, just regular interior lighting.
Has anyone experienced this issue? And/or is there some ingredient that could prevent this from happening?
I was wondering if Vitamin E could slow down the fading process? Right now I'm not using any preservative in my recipes.
Any input is appreciated!