FeOtot recalculation to FeO and Fe2O3 by stoichiometry

Hello everyone!

Would like to ask if you know about a "universal" method to recalculate FeOtot to FeO and Fe2O3 by stoichiometry? I know about a method of Carmichael, i.e. recalculation on ulvospinel and ilmenite basis, but it seems to be only for spinels (please correct me if I'm wrong).

Is there a formula for such recalculation for any mineral?

Best regards,

Luke

I calculate formulas in xcel-spreadsheats. I then put analysed Fe expressed as FeO* in one column. Then I have one cell for FeO (which is the value I play with) and one for Fe2O3.
Then "calculating" FeO and Fe2O3 is done the following way:
First your mineral must have some constraining conditions, i.e. total number of oxygens or cations, etc. which you have as a formula in one of the cells.
Then in the Fe2o3 cell you put the formula
(FeO*-FeO) x 1,11138
In the FeO-cell you now assign a value and check your "constraining condition cell" and adjust until it has the right value.

cheers

If you are starting with microprobe data, Lukasz, there isn't any one method that will work for all minerals. In some cases you won't know O:OH, for example, so you won't be able to calculate it at all by stoichiometry.

Thank you very much, Sirs! (-:

Its simple enough for many anhydrous minerals as per Johan, but minerals with vacancies or OH and undetermined elements can be impossible. Schumacher (1997) came up with a method for amphiboles, but it does not always give a good result (Can Min v35 p237-246).

Regards,
Ralph

Thank you, Ralph! Its all indeed not that simple..

Cheers!

Luke

We work with mineral(zircon sand) with Fe2O3:1.86% how do i calculate the separation of FeO from Fe2O3.what value will it give me?The report of the material is attached.

Best regards,


Egbo

Egbo, Unfortunately this is not possible without knowing the mineralogical purity of the zircon sand itself; in other words, what mineral is the Fe³⁺ present in?

I have been done Geochemistry of Sedimentary deposit/Red soil and found Fe2O3: 8.56%, how do I calculate the separation of FeO wt% from Fe2O3 wt%.

To determine the FeO/Fe2O3 contents there are standard wet chemical methods, based on the dissolution of the soil and titration to determine FeO, then determine Fe2O3 by difference from the total Fe.

Regards,
Ralph