This is not a "start-up" type question. Dubai lawyers don't participate on Avvo. You need a Dubai lawyer experienced in the field to assist you. Not only do you need advise on exports of gemstones, but you need to figure out the European laws on gemstone imports. Then you need experience about the trade/bank documents necessary to make sure you aren't paying for something that is never delivered. Letters of Credit with Certificates of Quality among other documents are normally used.
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
Not a US immigration law question.
Mr. Shusterman is a former INS Trial Attorney (1976-82) with over 35 years of immigration experience. His response to your question is general in nature, as not all the facts are known to him. You should retain an attorney experienced in immigration law to review all the facts in your case in order to receive advice specific to your case. Mr. Shusterman's statement above does not create an attorney/client relationship.
Frankly, as someone who has been there and seen the reality as well as doing some work jointly in Dubai, I can tell you, your buddy seems a bit lost. The gem markets in Thailand, Singapore, India are eons less expensive than one of the highest income areas in the world, the UAE. We had a client who deals in high end watches go there a few months ago and he thought he could find a steal, but found he could do better here and even better in Hong Kong, unless of course, you are looking for $1,000,000 plus watches.
Before researching the law, please research the markets. The laws don't really make that much difference and Dubai is not exactly what I would call a US style "far better than marginally functioning" legal system. Even the color of the car license plates tell everyone whether or not you are in a prominent or powerful family or not. Almost all the countries you listed have very entrenched system of "connected" folks going back centuries. You may be better of using a free market system like EBAY that has a secure payment system.... have a look at SIAMLAGUME on ebay.
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