experimentally determine oxidation state of Iron compound

I need to make several Iron compounds but I am having a bit of trouble finding a decent way to determine the oxidation state of Iron.
I'm starting with a Iron(II) compound that I try to oxidize using several methods. I can use raman to determine the compound but that requires me to create the compound I want to make and check that spectrum against my experimental sample. This is quite a bit of work and I was hoping someone could point me towards a better solution.
I can make an EDS but since my compounds usually contain carbon or oxygen as counter ion so EDS isn't very accurate. I don't (currently) have access to an XPS and I don't have unlimited access to a mass spectrometer (I have to travel quite a bit to get to one). 


Can someone help me find a better way to determine the oxidation state??




In all the (physical) experimental literature I've read, at least for biomolecules (usually enzymes), the technique of choice is [Mossbauer spectroscopy](https://en.wikipedia.org/wiki/M%C3%B6ssbauer_spectroscopy). [Here](http://serc.carleton.edu/research_education/geochemsheets/techniques/mossbauer.html) is a good starting point.


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[Here](http://www.fbioyf.unr.edu.ar/evirtual/pluginfile.php/109394/mod_folder/content/0/Standard%20Methods-3500-Fe%20en%20agua.pdf?forcedownload=1) is a link to the full *Standard Methods for the Examination of Water and Wastewater* method 3500-Fe for determining ferrous, ferric and total iron in aqueous solutions. 


Here is an excerpt describing the principle of the procedure: 



> 
> "Principle:  
> 
>  Iron is brought into solution, reduced to the ferrous
>  state by boiling with acid and hydroxylamine, and treated with
>  1,10-phenanthroline at pH 3.2 to 3.3. Three molecules of
>  phenanthroline chelate each atom of ferrous iron to form an orange-red
>  complex. The colored solution obeys Beer’s law; its intensity is
>  independent of pH from 3 to 9. A pH between 2.9 and 3.5 insures rapid
>  color development in the presence of an excess of phenanthroline.
>  Color standards are stable for at least 6 months."
> 
> 
> 


In this method, ferrous iron is measured directly and ferric is determined by difference between the total iron (measurement also described by method) and the ferrous iron. Obviously, when the ferrous iron concentration approaches the total the uncertainty in the the ferric iron concentration becomes large.


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