There are fake ads on Facebook that look like they are legitimate ready mixed concrete producers.  When you place an order, the scammers pocket the money.  The scammer will then place a concrete order with stolen credit cards and make it look like the order is coming from a reputable contractor. Concrete may be delivered to the job-site, but the ready mix company has not been paid.  Both sides are getting scammed.      

DO NOT use Facebook to purchase concrete.  Contact the ready-mix company directly to place any orders.