The essential oils we refer to as "precious" are those that require large quantities of plant material or undergo special distillation methods to produce the oil. This makes these oils more rare and costly. But the result is other worldly. Deeper, richer aromas and potent aromatherapy benefit.
For example, it takes about five tons of rose petals to make just a little over 2 pounds of Rose Absolute oil. When you want only the best, these precious oils are the ones to explore.