[header] How to test essential oils for purity [title] Compare the prices of the essential oils. [step] Some flowers or plants that essential oils are derived from require a larger quantity to create one drop of oil. For roses, it takes almost 60 roses to make one drop of oil, and this should be reflected in the price of the oil. 
An unusually low price is normally a sign that the oil is diluted in some way, making it less pure. [substeps] If all of the oils from a particular brand are the same price, it is usually indicative of less pure oils.