There are a couple of routes you can use for trading:
Just remember to look at house laws around trading, as an example only rhienland corps can move Military Salvage through Rheinland.
Molybdenum Ore <-> Iridium Ore
buy Molyb in Zurich
sell in Theta - PRIMARY - Edge Worlds - Omicron Kappa - Livadia Shipyard - Outworlders - $10181
buy Iridium in Omicron Delta
sell in PRIMARY - Gallia - Picardy - Haute-Seine Shipyard - EFL - $12182
return to Zurich for Molyb
Gold Ore <-> Aluminium Ore
buy Aluminium in Frankfurt
sell in New London - PRIMARY - Bretonia - New London - Planet New London - BPA - $10488
buy Gold in Dublin
sell in New Berlin - PRIMARY - Rheinland - New Berlin - The Ring - Daumann Heavy Construction - $9272
return to Frankfurt for Aluminium
Helium <-> Helium-3
buy Helium in Pennsylvania
sell in Sigma-59 - Niigata Star City - $13204
buy Helium-3 in Sigma-59
sell in PRIMARY - Liberty - New York - Planet Pittsburgh - Deep Space Engineering - $9830
return to Pennsylvania for Helium
Pristine Ice <-> Iridium Ore
buy Pristice Ice in Cortez
sell in PRIMARY - Edge Worlds - Omicron Delta - Nauru - Core - $13782
buy Iridium Ore in Omicron Delta
sell in Coronado - PRIMARY - Independent Worlds - Coronado - Sabah Shipyard - Crayter Military - $12606
return to Cortez for Pristine Ice
Molybdenum Ore <-> Platinum-198 Ore
buy Molyb in Zurich
sell in Honshu - PRIMARY - Kusari - Honshu - Yukawa Shipyard - Kishiro Technologies - $9046
buy Platinum-198 in Shikoku
sell in Zurich - PRIMARY - Borderworlds - Zurich - Oerlikon Stellar Observatory - EFL - $13921
You are now in Zurich for more Molyb!
Uncut Diamonds <-> Military Salvage
buy Uncut Diamonds in Omega-11 area
sell in Ile-de-France -PRIMARY - Gallia - Ile-de-France - Planet New Paris, Saint-Denis - Gallic Navy - $8458
buy Military Salvage in Gallia
sell in New Berlin - PRIMARY - Rheinland - New Berlin - Planet New Berlin - Rheinland Police - $10434
return to Omega-11 area for more Uncut Diamonds
Gold ore <-> Raw Hydrocarbons
buy Gold ore in Dublin
sell in Honshu - PRIMARY - Kusari - Honshu - Planet Honshu - Kusari State Police - $9929
buy Raw Hydrocarbons in Tau-53
sell in Cambridge - PRIMARY - Bretonia - Cambrigde - Portsmouth Shipyard - BMM - $11353
return to Dublin for Gold ore
Beryllium Ore <-> Niobium Ore
buy Beryllium in Omega-48 area
sell in New Tokyo - PRIMARY - Kusari - New Tokyo - Planet New Tokyo - Kusari State Police - $10240
buy Niobium in Tau-23 area
sell in PRIMARY - Border Worlds - Omega-3 - Planet Sprague - BPA - $10662
return to Omega-48 area for Beryllium