Brown stone contains more sand than stone

19mm Brown stone was orderred from Brights hardware over the phone and payment done via eft after invoice was received. Delivery charges was paid and stone was deliverred during working hours. Please note that this is the third batch of stone orderred from Brights. When we started using it we realised that the stone contained more sand than stone and in some patches it was only sand. I logged an enquiry on the e-mail address as per the Brights website on 27 November asking what their policy is when a product deliverred is not what was paid for. I received an email back from Monique at Brights asking me which branch the stone was bought. I informed her that it was the Stikland branch and she notified me via a return e-mail that she will ask the manager their to phone me. On 28 November I followed up with Monique as no one had contacted me. On 29 November I followed up again with no response. I have not received a response to date.