Doug Winter, of raregoldcoins.com, just posted an article titled "What Do Original United States Gold Coins Look Like?". A good read, illustrated with six examples.
Those are some pretty coins. I have no basis to judge the "naturalness" discussed, but the coins themselves are gorgeous.
For those interested in the gold coinage of the US, Mr. Winter's website is a cornucopia of knowledge. http://www.raregoldcoins.com/category/articles
