Royal Oak at Wallyworld seems to be the most economical. I think it might be a 10lb bag for $6.50 (might be lil smaller bag...not real sure).
Kroger sells an 8.8lb bag for $6 (they put it on sale about every other week for $5.50). I heard that the Kroger brand might be RO lump. Not sure.
Seems everything else is at least $1 per 1 lb.
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