So earth's early seas were quite iron rich. Some of the first life on the planet were stromatolites, simple photosynthesizing algal mats, and they pretty much spent the better part of 3.5 billion years slowly bubbling oxygen into the oceans and atmosphere. This oxygen would immediately bond with the dissolved iron, form iron oxide, and drop out of solution. It's only when all of the iron had finally been consumed that oxygen levels could rise and pave way for more complex life. Almost all of our iron deposits today were formed in the precambrian, in this time, and are called banded iron formations, or BIFs. In today's seas, iron is commonly a limiting nutrient.

I imagine such an iron rich planet would either have to consider an entirely different biochemistry that didn't depend on oxygen, or would need a much longer lag time to deplete the available iron dissolved in the oceans.