I get offers from India all the time for my naturals. They always insist upon a certificate, yet offer a wholesale carat rate (ridiculously) far below the cost of the certification itself.
Needless to say, I won't be selling any naturals in India any time soon. The only likely source are Persian Gulf naturals by volume, but at the going rate offered, cannot be very profitable.
While I've seen a few nice pieces from India, I'd be wary of anything purporting to be naturals from that country.