Phil,
Your reply made me curious so I did some research. This is what I found:
Virgin oil is the result of a single, simple pressing; in contrast, cold-pressed is a marketing label rather than a processing technique.
Extra virgin is the highest quality olive oil -- characterized by "perfect flavor and odor, max acidity (oleic acid) of 1g/100g - 1% with maximum peroxide value mequiv 02/kg of 20." In some regions, extra virgin oil is judged by a panel of experts for taste, mouth feel, and aroma. This oil tends to be most delicate in flavor, and is preferred for salads or served at the table with bread for dipping, or added to soups and stews.
Fine virgin oil is just slightly less perfect -- with "maximum acidity (oleic acid) of 2g/100g - 2% with maximum peroxide value mequiv 02/kg of 20."
The other officially designated grades of olive oil are the result of several chemical refining and blending processes:
Semi-fine or ordinary -- suitable for cooking when subtle flavor is not required.
Refined -- maximum acidity of .5g/100g, lacking the flavor of virgin oil.
Pure -- a low-cost blend of refined and virgin, such as you might find in large quantities at a discount food warehouse.
Pomace refers to the pounded olive residue. Refined olive-pomace oil and olive-pomace oil are lower-quality oils.
Pomace oil, olive cake, and lampante (or lamp grade olive oil) are not intended for human consumption, and are generally used for industrial or technical purposes, such as soap making.
On Jim Dixon's Real Good Food site, we learned that these chemical and flavor standards were first established by the International Olive Oil Council in 1990, and have since been applied to California olive oils as well as Southern European varieties.
doc (never too old to learn something new!)
