Many soapers and crafters got into their craft because they wanted to make and use the most natural products possible, and to be able to control what ingredients are in the products they use. One way to do that is to use herbs and other natural colorants in products. They can be a bit unpredictable, but are also fun to use and can yield some very beautiful results.
Here are some natural colorants to use that will yield blue, purple and grey tones in your product:
Alkanet root (dried, infused in oil) – maroon to indigo. Begins mauve/lavender, turns pinkish. Very pH sensitive.
Beet root (dried) – soft pink to red to purple, depending on amount used
Bentonite (clay) – beige to green to grey
Blackberries (dried or pureed) – purple to blue
Blue Chamomile essential oil – robin’s egg blue to light green
Glacial clays – grey to brown
Hibiscus, red (dried or powdered) – purple
Indigo root (infused in oil) – deep blues. Caution – can stain
Mulberries, black (pureed or dried) – red violet to dark bluish purple
Myrtle berries (pureed or dried) – maroon to purple
Oregon grape berries (pureed or dried) – purple
Pumice, ground – grey. Adds abrasiveness to scrubs, gardener’s soaps, kitchen soaps, etc.
Spirulina/blue-green algae – bluish green
Woad leaves (dried, infused in oil) – blue