German to English Art/Literary Art, Arts & Crafts, Painting

This is one of three (somewhat overlapping) strains of modern art referred to in my source sentence:
"Die visuelle Kunst des 20. Jahrhunderts hat daher – neben der Materialmalerei, der Objektkunst und Installation – neue Handlungsformen der Kunst hervorgebracht"

Basically we're talking about "painting" using nontraditional materials -- as the term is used here, for example:
"Bezeichnung für Bilder, die aus sonst unüblichen Materialien (Pflanzensamen, zwischen Glasplatten befindlichen verschiedenfarbigen Sandschichten, kleinen Steinen, Glasstückchen, Stroh etc.) bestehen."
http://www.beyars.com/kunstlexikon/lexikon_5832.html

And here:
"Eine Materialmalerei, ganz ohne Ölfarbe und Leinwand, nur mit leichten Stoffen und Glas"
http://www.neuegalerie-archiv.at/stiege/98/motschnig/motschn...

The search results I've gotten for "material painting" have been a mixed bag -- a lot are irrelevant, others (from the English-language versions of German websites) are questionable, but a few (mostly references to the Catalan painter Antoni Tàpies, translating his term "pintura materica") seem to be on the mark.

Anyone know a better term for this, or is "material painting" as good as it gets?

PS: I've already seen this: http://www.proz.com/kudoz/german_to_english/art_arts_crafts_...