just a tip for owners of Avorio leather interiors, to match the colour use an acyrlic cream colour and then mix slightly with a yellow ochre colour, gives a perfect match.
what do you mean 'of what substance' i dont get the question, i had the feeling when i posted my tip it would be shot down in flames by a more "senior member', I'm sorry i mentioned it now.
Seemed like a reasonable question to me, and not 'shooting down in flames'; I had the same initial thought. Are you adding acrylic paint to leather polish or something?
I got a good match from an eBay provider after sharing an avorio leather sample (2005 GT). He should be able to provide more on demand now he has the mix. Worked a treat on my driver seat bolster. Let me know if interested.