Hi Applewhite
The perfume and fragrance industries prefer nature identical oils - these are reconstituted oils from other e.o constituents which creates a similar odour or flavour to that found in nature.
There are also rectified essential oils that have been redistilled to comply with the British Pharmocopoeia standards, an international benchmark.
Pure essential oils should only refer to genuine, authentic, unadulterated oils without synthetics, or additives - so when you choose them always look for the botanical name, the country of origin, extraction process and part of plant use.
These are further categorised as
certified organic oils,
wildcrafted
and oils that have been grown using pesticides, herbicides and agricultural chemicals.
I hope this helps - have you given us the question in full, as it seems a little vague.
Binah
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