Additionally, there are always exceptions. Woodsy oils generally blend well with all categories. Spicy and oriental oils blend well with florals, oriental and citrus oils. Be careful not to overpower the blend with the spicy or oriental oils. Minty oils blend well with citrus, woodsy, herbaceous and earthy oils.
Some essential oils evaporate more quickly than others.
As the oils in a blend evaporate, the aroma will change to reflect the aroma of the remaining oils. Using the analogy of a musical scale, oils that evaporate the quickest, usually within 1-2 hours, are called top notes. Oils that evaporate with 2-4 hours are considered middle notes. Oils that take the longest time to evaporate are referred to as base notes. Another contribution to the field of odor classification was made by the famous perfumer and perfume historian, Septimus Piesse.