All essential oils contain some of each class of components.
Some have a higher concentration of one or another. For instance, frankincense has higher percentage of monoterpenes and sesquiterpenes. Oregano and thyme have high percentage of phenols. When we LAYER oils as in Raindrop Technique, the body chooses what it requires from each oil. Note: when oils are combined as in a blend, they chemically interact with each other and totally change the compounds. The Young Living blends are tested and must have the intended compounds in the blend itself. When we create our own blends at home, we have no idea what compounds are actually present.