Ok, so setting up a trade circle on purple, will have 6 bonus resources.
Currently we have the following people in the circle
Aluminun --- mydogti
Lumber -- Legend1990
Wheat -- DarkNoble
Water -- midna
Marble -- midna
Iron -- Legend1990
Lead -- mydogti
Rubber -- Lucas Perry
Oil -- DarkNoble
Coal -- Lucas Perry
Fish -- rstat1
Uranium -- rstat1
BRs are Beer, Construction, Steel, Scholars, Asphalt, Cars
According to the Resource tool in game my nation will receive the following increases, your mileage may vary.
Income: +$3
Citizens: +8%
Happiness: +9
Infra Cost: -35.2%
Tech Cost: +-0
Land Cost: -10%
Land Bonus: +38%
Environment: +1
EDIT: This is of course a purple circle, that is now complete.