Im thinking about building my 30x40 shop with stone. $12 ton is the rate for stone here. Seems it will be alot less $ than poured concrete walls. Am I missing smething? I have lots of time, so thats not the major issue. Thanks A yard of concrete is about $75 and weighs 3700lbs. 3700lbs or stone will cost me about $23 and may be $35 per 3700lbs. with mortar.