I make a Rosemary Mint soap quite often, with ground mint and rosemary and EO's . The herbs don't color the soap, and actually turn kinda brown, but I grind them up fine so it gives the soap that 'herbal' look. I color the soap a mint green. I'll post a pic when I can find one. I use ground herbs- chamomile, calendula, mint, lemon balm, rosemary, lemon verbena, etc.- in alot of herbal soaps, just for the look, they don't really add any color or scent. Although the calendula does hold its yellow color and looks really nice.