Praying on clay stones (“Turbah”) is an ugly Shia Bid’ah
What makes their Bid’ah even worse is that they don’t even consider the soil of Makkah or Madinah (Prophet’s علیه الصلاة والسلام soil!) as the best soil, but rather the soil of the cursed land of Karb (agonies) and Bala (afflictions). Thus, their Ghuluw is not even with the Messenger of Allah (s), but with his grandson.