Mainly oil on canvas.
Paints, pastel's- I think he also used crayons
During his years in Munich he was an expressionist. Later, in Russia and wit the Bauhaus, his abstract paintings were close to Suprematism.
All his pieces were done with Oil on either canvas, board, or cardboard
Because he was an artist, he thought that if he didn't include either shapes or colours, that his art wouldn't sell. He was right.He put colour on the canvas in various shapes and made a bundle.