Essential oils are the concentrated form of plants and spices in a natural oil. Used for centuries as plant medicine, they are often effective when the product is high quality.
The most important things to know about any essential oil are what is its source, how is it extracted and is it organic. As it takes 100 pounds of rose petals to make Rose Oil if the plants it is extracted from are not organic then the result is the concentrated forms of herbicides and stigmatic pesticide in the oil. As a result, rose oil, which is used in some cosmetics, is very expensive and can be toxic to your skin in application. You can tell by the scent it leaves behind.
Always follow your nose in choosing essential oils. Your olfactory senses know fact from fiction. If an oil burns your sinuses it is not “real.” Some oils are actually perfumes infused in an oil.
One great test is to take Lavender oil of the same species (there are many species) from various producers. Put a few drops of one on a piece of cotton. Sniff it, notice it, then clear your olfactory by sniffing either your skin, a clean piece of cotton or coffee beans. Without clearing the lavender scent the next test will smell like the first. Then do the same with the next sample. Notice the difference in the second oil, again clear the scent and try a third or as many as four samples to get a sense of the quality and compatibility with your system. One person’s favorite will not be the same as another’s. And one person’s favorite oil depends on what the person needs at that time. It will change over time.
Another other factor affecting quality is the availability of the plants the oils are made from. For example, Sandalwood has been over harvested as it is often used in many temples to create sacred space. As a result it is difficult to find an honest, clean source of sustainable Sandalwood oil. Some producers grown their own plants.
In general, choose wisely, know your source and if it is a clean source. Also, be cautious around blends as they can harbor poor oils that are in low supply.
Finally, as the olfactory senses are a direct feed to the brain, be kind to your mind.