Jin Pratima Base Figure

Whenever I observe any beautiful old Jin idols then a particular thought comes to my mind that a murtikaar can only develop an idol when he first sees the god who is to be carved in stone. Particularly one first has to see how the person looks like and then only carve an idol similar to him!

On that basis, on whom was the first Jina idol based on in this Avasarpini kaal?