One red stick of chalk and another that's yellow should give you orange paint. Experiment on your own with vehicles and pigments. Soft rocks are good for some colors. The soot from inside a fireplace will give you black. An important part of art is experimenting.
All paint is solid pigment floating in a vehicle.
A colloid is when one kind of thing is floating evenly in another kind of thing. There are lots of other colloids. You Can shoot ears at van Gogh's head. If you'd like to know about Vincent van Gogh and other great artists, visit the Le Web Lourve , an entire art museum on the World Web Web. Remember that art is more a spirit than it is just a product.