The VMS ink is NOT iron-gall

[oshfdk]

What do you mean by "sealant"?  And pigments are dry powders; do you mean "paint"?

By sealant I mean any kind of material that can be used to make things water tight, any kind of tar or sealing wax. By pigments I meant paints, yes.

There is no film.  The texture of the vellum is clearly visible and unbroken across all those stains.  Some of  the stuff may have remained trapped at the bottom of the pores of of the vellum, but the orangish color of the stains is mainly due to stuff that soaked into it while liquid.

This is not the way I see it. To me it looks like the vellum is covered in something. I don't think we can tell without a macro image.

Ah, so that is why you are so keen on the ink being IGI.

I think you believe for some reason that I'm on a mission to fight MRT. I'm not on a mission, but my hobby is about sorting what we know from what we don't know. Here I insist that we don't know that "the ink is NOT iron gall". You have a lot of weight in the Voynich MS community, so when you state something as a fact, but which appears to me very dubious, I would likely try to understand why.

MRT does not require the ink to have any particular composition.  It assumes only that the ink had faded substantially by ~1630, to a point that threatened to make the text illegible.  

And the ink obviously has faded in many places, to the point of invisibility.  That is not a deduction from some theory about the ink's composition: it is just an objective observation.

We know that it's faint, we don't know exactly when and how it became faint. If there was some flaw to the ink from the beginning it's quite possible that some parts just didn't react with the vellum well enough and never got to darken. I'd say this just looks like very poorly mixed ink and/or poorly prepared surface of the vellum.