From the ground pigments, I have been experimenting with making my own watercolors with gum arabic and honey.
Then poured into tins to dry.
They seem to dry at different speeds, depending on the pigment and some crack more than others. I have no plans to make paints to sell so these nuances aren't really something I am interested in figuring out.
The main thing I've been experimenting with is using my own homemade and foraged pigment paints directly on wood.
Testing for saturation, lightfastness, sanding-fastness (not sure if there is a word for this? absorption maybe? it's testing how much paint actually absorbs versus stays on the surface and gets removed from sanding) and of course testing how they interact with different sealers on top.
This is not something I could have experimented back when I was making toys as there is no way to claim that the paint used is non-toxic even if it is. Back then, it was easier to use a manufactured paint, even though the pigments were synthetically created.
I'm kicking myself that I didn't have this interest in earth pigments when I was in Pompeii two years ago. I mean, they were everywhere!
There even was a pigment shop there, with jars of pigment intact. Above photo isn't it though, this was a food stall we're standing in.
Speaking of history, many historically used paints ARE toxic. Lead white anyone? It was a classic white paint formula, in fact the Mona Lisa is full of lead as were most all paintings until the 19th century. Not to mention cobalt and cadmium and so on.
I am focusing on safe ochres and earth pigments and staying away from anything toxic, obviously. Oh and relying on indigo for blue but more on that later. I've also been making organic lake pigments (which is dry powder pigments from plants, basically) but selecting only ones that show good lightfast tests which isn't many.
So much more testing to be done!!
Fortunately, there is plenty to explore right nearby.
It is quite a rabbit hole of exploration to jump into but one that combines rock hunting with making art - both things I do anyway.
PS - to jump down the rabbit hole of ochre pigments yourself, Heidi Gustafson is a good place to start. Seriously eye candy of color.