Snapdeal.com - Used,defective gem(opal) delivered and after lodging complaint snapdeal team refused to either repla

I orderd a gem(opal) on snapdeal and received it on **th Sep **** but I found it complete different from what it was shown during booking.Moreover the gem is an used one and havingmore than one scratches which will harm the wearer and bring misfortune.The same day I lodged complain for either replacement or refund but no steps,cooperation from snapdeal and suddenly they rejected my appeal.What I will do with iyt now?What was my fault?Why I am victimised of fraud?I want my full money back and would return it asap.What snapdeal did is against all business moral,ethics and values.I am cheated.I want my money back.I want justice.I want to lodge my complaint.