Regarding the hiddur of using olive oil to light
Hanukah candles, Maran HaRav Eliashiv made known previously
that the closer the oil is to the olive oil used for the
menorah in Beis Hamikdosh, the more
mehudar it is for Hanukah.
Therefore the types of olive oil sold today fall into the
following four different classifications, listed in order of
the level of hiddur.
1. Pressed olive oil
2. Fine olive oil (the refining process lowers the quality of
the oil)
3. Oil made primarily from olive dregs and which is edible
4. Oil made primarily from olive dregs and which is
inedible
This ranking is only to determine the level of hiddur
mitzvah.
In his weekly shiur last week on Kol Haloshon, HaRav
Efrati discussed in detail Maran's opinion regarding the
quality of olive oil and the levels of hiddur.