&gt; Stone is way more common<p>Stone is literally more expensive than oil. Note that at $2.00 &#x2F; gallon, gasoline (refined oil) is twice as cheap as bottled water. At $35 &#x2F; barrel (ie: $35 per 55-gallon drum), crude oil is literally cheaper than a huge number of commodities.<p>Crude Oil is roughly $0.65 per gallon. Definitely cheaper than stone by every measurement.