Diamonds are high value commodities as we all know. Rough diamonds cost as much as $1000 per carat - a carat being 200 milligrams. A cut and polished diamond fetches 20 times more than the rough diamond from which it was formed.

My question is: How does one control what happens inside a polishing factory?
1) as an owner and
2) as a customer who supplies the rough diamonds and pays for the cutting and polishing service.

There are losses. That is expected, but how do you set up a control system to prevent you from being taken to the cleaners in the 2 cases mentioned above?

I read this article and smiled inwardly as I imagine CA's running around trying to get a handle on what looks like a chaotic situation.

Nine out of 11 diamonds in India are cut and polished in Surat, where nearly 450,000 diamond cutters and polishers work in nearly 4500-odd factories in grossly unorganized small and medium-scale.
The complete article is here