Making gum prints with ashes

Anybody any experience with using ashes from cremated people for gum print? Perhaps it's a strange question but in the near future I might have somebody that might ask me to do this with a photograph from the deceased. She knows I'm into alternative process and a few years back we chatted about using cremains for alt process, I told here that it should be possible to do (although one should probably mix in some pigment too) but it was more a brain doodle than anything else. It's perhaps a little controversial to say the least but perhaps somebody has more experience in this?

A woman I know does this; she's not terribly forthcoming with details on how she does it, though. I'd buy some beef bones and burn them to ash and use that as a test.

Bone black is/was made out of charred bones http://www.webexhibits.org/pigments/indiv/overview/boneblack.html
I would mix the ash with other pigments like bone black. There is also a bone ash White which is usually used as filler medium for other White pigments.
So basically it should be doable.

Rather than gum, might I suggest "carbon" prints - By mixing the ashes in a gelatin support, you'd get a thicker layer that should give more depth to the image. As the "pigment" (for the want of a better word) would be white to light grey, a black paper would probably be needed.