Pressing: Extracting oil from the plant by applying pressure. Citrus Oils are usually extracted this way.
PC: Pressing, Cold: A certain amount of heat is used to help release the oil, usually not higher than 60-80oC (140-176oF). Above this temperature the process cannot be classified as cold expression.
PH: Pressing, Hot: In hot expression, temperatures can go up to 200oC (392oF).
Stretching: Adjusting or altering the oil. This is a legitimate practice in food processing & perfumery to stretch or standardize the smell or taste of an oil.

SN: Stretching, Natural: Stretching by adding natural products such as alcohol, terpenes from other oils, cheaper oils such as lemongrass in citronella, or Lavandin in Lavender.
SS: Stretching, Synthetic: Stretching by adding a colorless or odorless synthetic product such as adding synthetic Thymol to Red Thyme.

V Solvent Extraction: Extracting delicate oils that can be damaged by distillation or other methods using solvents to dissolve the oils.
VC: solVent extraction, Concrete: Plant materials such as leaves, flowers, roots, or stems are dissolved in hydrocarbons, usually Hexane producing a solid, wax-like material after removing the solvent. Rose concrete is an example.
VA: solVent extraction, Absolute: Absolutes are extracted from concretes using alcohol which is later removed. Violet Leaves is an example.
VO: solVent extraction, Oil: Plant materials such as seeds are first crushed and dissolved into solvents. Hexane is the most commonly used. The solvent is evaporated under vacuum to yield the oil. Black Cumin Oil is an example.
VR: solVent extraction, Resinoid: Resinoids are resins dissolved in a solvent such as benzene or alcohol. Resins are natural solid or semi-solid substances produced by plants or trees. Vanilla Oleoresin is an example.
VW: solVent extraction, Water soluble concentrate: Oils are first extracted with alcohol, then the alcohol is removed leaving the oils suspended in a water base. The alcohol trace left is comparable with alcohol-free drinks. Vanilla concentrate is an example.
VE: alcohol Extraction: Plants are soaked in alcohol and water—some essential oils will be present, but extracting is primarily water and alcohol.

Grades:
GK: Grade Kosher: Certified, Chief Rabbinate of Israel.
GO: Grade Organic: Certified by Independent 3rd Party.
GP: Grade Premium: Pure and Natural. Not reconstituted nor blended.
GS: Grade Standard: Modified or Enhanced for Commercial use.
GW: Grade Wild: Grown/Collected from the Wild.

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