Valentinčič was born on 16 May 1950 in Postojna. He studied painting at the Ljubljana Academy of Fine Arts (1972-1977, under Professors J. Bernik and A. Jemec). After graduation, he worked in a library in Ljubljana. His painting belongs to the context of primary and analytical art. Initially, it was dominated by a grey colour that dissolved in horizontal and vertical strips. In the second half of the 1980s his work was marked by the colour image, and characterised by elementary, direct expression and creative isolation.

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