Vibhuti aka the Holy ash for the Hindu’s in this part of India is very sacred. The most famous supplier of these Vibhuthi is Palani Parimala Vilas Sithanathan & Co. They’re very famous for their fragrant Vibhuthi’s along with the Panchamirtham. The same is available at Purasawalkam High Road near Thana Street. (it’s 89 years old now)