The process of obtaining prickly pear seed oil is quite tedious, normally taking three or four days.
Since the seeds are tiny, they must be carefully picked by hand. Also, only about 18-20% of the peeled fruit are seeds, and the seeds only contain about 3-5% oil. As such, it takes a ton of this cactus' fruit (literally a ton) to produce barely a liter of oil. Not to mention that the fruit harvesting season only lasts a few weeks to a few months (depending on the region).
As for the oil manufacturing process itself, the prickly pear oil we use is obtained by cold pressing, refining and standardization with non-GMO vegetable oils to improve oxidation stability. It then goes through a filtering and purification process. This helps eliminate any unwanted odor or color and improves the shelf life of the oil.
Now you understand why prickly pear oil is the most expensive oil in the world, justifying its rather expensive price! Thus, beware of companies that will make you dangle a prickly pear oil at very low prices because it will very often be diluted and of very poor quality!