ice cream and olive oil

So I love the flavor of lemon and I recently started preserving lemons. I saw someone on Instagram do it and they just chopped up a lemon in slices and then they put it in a jar, sprinkled some salt on the lemon, like one slice at a time, sprinkled salt, next lemon slice, sprinkled salt, on and on, up in, and then they poured olive oil just over all of those lemons and let them sit.