Thanks duchess for your comments....there is a difference in natural occurring monoterpenic molecules which are balanced by the rest of the plant materials making up a natural whole. Example; the real rose petal will hold its fragrance (essential oil) even when it dries, while the synthetic chemical copy of "rose petal essential oil", with each chemical made separately & combine with other synthetic chemicals to copy the natural whole, will oxidize if left open to oxygen...thats the behavior of petrochemicals....hope that helps...but I always like to encourage to do your own research, do dive deeper into this, just remember the term Essential Oil is interchangeable with both organic & in-organic chemistry.....many thanks, I really appreciate your question...and I am always trying to prove myself wrong, so feel free to help me out....many thanks....much Peace2U;)