While some of these resources surely have a high value, it is important to note that the location of your capitol influences the base value of the resources.
I.e. if your capital is Arhus, you will not get any thing decent for fish and amber, regardless where you mine these. If your capitol is Frankfurt, you get a lot for amber and fish on the other hand.
Similarly, setting your capitol to be in the Middle East lowers the value of gold and ivory, even if found in Africa.

Everything is relative.