He loved them. That is why he went on doing them.
Geometrical ones. Click link below to see some of them!Piet Mondrian painted all sorts of paintings, type in Google "The Red Tree by Mondrian" or "The Grey Tree by Mondrian" or "Blooming Apple Tree...
The largest Mondrian collection from his whole career is in the Gemeentemuseum, the Hague, Netherlands.
He painted in oil.
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