I think this is more like Plasticine (one type of which is Play-Do), vs. earthen clay (lick used to make flower pots). I used it for the first time last week. I bought two bars of it (180 Grams each), 3M brand (type 38070, from memory)on eBay. The two bars were $US11.50, free shipping from Korea. There is a YouTube video of a guy using it, and it seemed to work fine. I used Chemical Guys' Luber product (made specifically for use with clay bars) as a lubricant vs. the quick detailer type products (about half the price of Meguiar's Quick Detailer) from a local detailers's supply place. I know that the 3M products are used by body shops all the time, so I felt pretty confident in it.
I think it is a synthetic, chemical product, not a natural one. I don't know what abrasives are used, but even in the 3M clay that I used, rated as a medium, its a pretty fine abrasive.
I used about a third of the bar and followed everybody's instructions on how to use it (knead it into a ball, then after it starts to soften due to body heat, form into a patty shape big enough to cover your four fingers). Then spray the lubricant onto the car surface and rub away. I probably used more lubricant that I should have, due to not being familiar with the use of the clay bar, and thereby being very cautious.
