Need help locating International Brokers or bulk buyers

I need help finding international brokers in Japan, China, Europe and even the USA please. If they are in China I’d prefer they do proper business with 50% down and 50% upon receipt. I’ve just recently had a massive deal fall through and created new products through heating this particular gem that had never been done. I have the mining licenses and export licenses needed to legally do business on an international level and can even export industrial materials. I just need someone who isn’t a crook and can do business in a realistic manner. Why would a company send stones without any sort of payment upfront. My current broker in China expects this on a 10 kilo per month supply of stones. Can anyone help point my in the right direction. I will make it worth your while.
Kindest Regards,