Depending on which variety of arkansas, they can be nearly impermeable or .. not. The translucent and black are nearly impermeable and the rest are .. not.
FWIW it's been 40 years since I put oil on a rock, and I use arkansas burnishing stones several times a week.
To the best of my knowledge 90% water and 10% generic dish detergent will do for lubricant on any sort of hone. It's quite possible other liquids are superior, but oil isn't one of them. I've gradually, over the course of the last decade, stopped using water (alone) because the detergent mix works well and seems to minimize wear on the knives AND stones.
I make no claims regarding RAZORS and diluted detergent; kitchen knives and personal utility knives are my primary interests and the bulk of my experience.
Easy-Off oven cleaner will remove oil, as will soaking in a crockpot with some strong cleaner (powdered dishwasher soap). Use low heat, start with rocks and water both cold/room temp; and don't touch the rocks till they've completely cooled down. Boiling them out is risky and sudden temp changes will crack them EVERY time.