Toning with pigments

The cave paintings in europe, that have lasted so many thousands of years are made from mineral pigments mixed with animal fats. I'm wondering if this is a viable way of toning prints and if anyone has done this before.

Moersch mt4 appears to be a sulfide toner containing red ochre aka iron oxide.

Instead of using fat, I would probably use glycol as a carrier as it is more soluble with gelatin. Tone first with sulphide. Then a second toning with the pigment. Ochre, ultramarine, the choices are endless.

Is this something that has been experimented with before (besides Moersch)?

Glycol absorbs water from the air so not a good choice. Pigments will not change the color of the black silver image and are opaque. You would need a dye which would color all but the image. The cave paintings are EXTREMELY fragile and not capable of holding up to today's environment. Even the presence of people in the cave degrades them. The moisture from their breath is enough.