One should prepare the Ganesh idol from china clay or mud. Nowadays, idols are made from plaster of Paris so that they become light weight and more attractive. There is a difference between idols made from mud and plaster of Paris. There are references in the Purans (mythological texts) that Ganapati was created from grime. Hence it is appropriate to use a Ganesh idol made of mud for ritualistic worship. The pure spiritual particles (pavitraks) of Ganapati get attracted to a greater extent towards an idol made of mud than to that made of plaster of Paris. The following points shall illustrate how it is improper as well as harmful to make idols from plaster of Paris or from substances other than china clay.
Plaster of Paris does not dissolve easily in water and hence the idol floats on water after immersion. Sometimes in cities, the remains of idols which have not dissolved in water for a long period are collected and a bulldozer is run over them to convert them into mud. This amounts to extreme denigration of the deity. The deity should be offered the same reverence when immersing it as when it is invoked. Since the idol is not immersed properly, in a way it amounts to dishonouring the deity. It is beneficial if a hole is kept at a specific point on the rear side of the plaster of Paris idol so that during immersion it gets properly immersed in water within minimal time and dissolves completely.
Mixing of the plaster of Paris in water pollutes the river, sea, lake, etc. and can have an adverse effect on the health of living beings.
Nowadays a wrong trend has set in whereby idols are even made from coconuts, bananas, betulnut, silver, coins, etc. Some of these objects do not dissolve in water after immersion of the idol. The remains of such idols are used for other purposes or as toys by children.
Many idol makers get the spiritual experience of the God principle when making idols of mud rather than of plaster of Paris. The spiritual experience of an idol maker is given here as an example.
\'I made idols of plaster of Paris as well as clay for the Ganesh festival. I experienced immense Bliss (Anand) when making idols of mud. So also my repetition (chanting) of the Name of my family deity (kuladevata) was occurring continuously. I did not experience this when making plaster of Paris idols
.\' - Mr. Lakshman Ahoman Chavan, P.O. Dhule,Maharashtraeco friendly ganesh