If you have a suitable reference material, then yes, this is how you would go about it. But I would recommend checking out some of the papers from CODES where they spent a lot of time working with sulfides and looking at correction factors for dealing with the different sulfide minerals (e.g. pyrite vs sphalerite etc). For example:
https://pubs.geoscienceworld.org/gsl/geea/article-abstract/11/1/51/128929/Routine-quantitative-multi-element-analysis-of
And I think there is another one talking about individual correction factors.
Anyway, please let us know how it goes.
Kind regards,
Bence