MITRA Forum Question Details

It would really depend on what you need for a final effect. If you intend on burnishing, like a medieval illumination, you would generally need a bulked up animal glue based mordant (or one of the curious variants including garlic juice, etc. I have not tested these but may work this into an advanced undergrad seminar or such).

If you are simply attempting to adhere gold leaf (or another metal leaf) to paper one of the polymer gold sizes should be appropriate. There are a few on the market (Wunda, Aqua, etc.) Probably any acrylic dispersion medium would work depending on your particular need (ie open time requirements, and flexibility).

One word of caution here....you should likely perform some tests on your intended paper substrate as any water-based adhesive/mordant could potentially cause some wrinkling and/or planar deformation, particulaly is the paper substrate is thin. 

You could apply a size to lessen potential planar deformation but if you are careful and test, this may not be necessary. Additionally, if you do use a size, make sure that it is compatible underlayer for your chosen mordant. Oil mordants become very brittle, making it inappropriate for use on a flexible support like paper. In addition, as oil gilding is not burnishable, it offers no advantages in this circumstance other than a longer open tine.  

I have not personally used that system. You do point out one of the shortcomings of polymer sizes. They gel so quickly that artifacts from the brush strokes are difficult to avoid. Kolner advertises that their product is sprayable. That would certainly avoid this problem. In addition, they do suggest a size (they mention shellac but this seems to be in relation to gilding architectural interiors, this would not be appropriate for paper). Sorry that I was not more of a help. Perhaps others have more salient comments.

I just read the directions for Instaclay provided by Kolner and it says that if you have drips you can remove them with sand paper. Have you tried that?