There are a lot of herbal / essential oils on the market, many which are touted as effective against acne:
Volatile essential oils: Tea tree, thyme, eucalyptus, lavender, neem etc.
Non volatile herbal oils (that don't smell): Tamanu, Calendula, Jojoba, Grape seed, Macademia nut etc.
I've seen some clinical trials comparing in vitro efficacy of some essential oils, I believe thyme came out on top against e.g. tea tree, but I'm wondering if anyone here have experimented with pure oils and if, noticed any difference? Between the volatile oils and between the herbal non-volatile ones (which would be fine to use in pure form).