In the ancient world oil was extremely valuable and there were many types. Vegetables produced oil and so did animal fat, but the most popular was olive oil and there was an abundance in ancient Israel. The oil was produced after removing the seeds from the olive and then squeezing, trampling, or pressing with a heavy stone. The best oil was used for burning lamps, cosmetics, and anointing oil.
Oil was stored in earthenware vessels (Heb. Asak). They were deep and narrow, with the narrowest part at the bottom. They had no handles and were usually inserted into a stone or wooden stand, or simply placed into holes in the ground. The top was capped with wood or some soft material. There was also the pitcher (Heb. Amphora) which was used for carrying oil, wine or water. (See Mark 14:13 and Luke 22:10).
"And Elisha said unto her, What shall I do for thee? tell me, what hast thou in the house? And she said, Thine handmaid hath not any thing in the house, save a pot of oil."