Using Historically Unconventional Materials - Europe and America

IMPACT OF ARTE POVERA MOVEMENT
The Arte Povera Movement started in Italy (hence the Italian) after WWII.  It began about the same time that Abstract Expressionism exploded in America.  Some writing about Arte Povera dates it to the 60's.  I think it began earlier than that.  The link for Arte Povera is a good, short, overview of this movement.

As far as I know, this was the beginning of what is now quite common - using materials to make art that are not historically used to make art.

SELECTED CONTEMPORARY EUROPEAN ARTISTS - UNCONVENTIONAL MATERIALS
The list of artists on the Arte Povera link is not a thorough one. Three artists I'd like to focus on, that I see as doing work consistent with this movement, are Antonio Tapies, Antonio Clave, and Anslem Kiefer.   Click on the links to see some images.

Tapies and Clave are from Spain and Kiefer is from Germany.  They each have extensively explored the life around them, it's history, politics, and culture.  Kiefer who now lives in France has used landscape as part of his exploration of German history, including a fair amount of focus on the Holocaust.  To help carry their message, they each combine found and/or discarded objects in their work.  This can range from paper, plants, ladders, tools, to more risky materials like lead.  I find each of their work breathtaking. They just are stunning.  I find Tapies' work to be more remote, more intellectually challenging, than either Clave's or that of Kiefer.  Kiefer's works are usually monumental in scale and they can just suck the air out of a room.

SELECTED CONTEMPORARY AMERICAN ARTISTS - UNCONVENTIONAL MATERIALS
The Abstract Expressionist in America also used unconventional materials in their paintings.  Though, they carry a different emotional weight than the Europeans.  American contemporary 2-D art is thought of as having a great concern with surface.  There's also an optimism that comes through in contrast to the Europeans.  Though, at the same time, the American work in my view has less sense of history about it, with some exceptions. Many more artists and movements followed who continued using unconventional materials.  Here are but a few names: Jim Dine, Kiki Smith, Julian Schnabel, Robert Rauschenberg,  Eva Hessse, Frank Stella,  Julian Schnabel, Dove Bradshaw, Red Grooms, and Cy Twombly.  Today, anything goes.

ART AS PROCESS
Another theme connecting these works is the theme of art as process.  Modern contemporary art has this thread running through it, to lesser and larger degrees.  This shows up in Diebenkorn's work as a road map of his creative process of reworking a painting.  It shows up in the works of John Cage and Dove Bradshaw as the point of their work - exploring time, chance, chaos.  One can also throw in the performance work of such people as Rauschenberg who explored performance as art at its inception.  Kiefer's and Tapies's finished work manifests a great deal of process, with some Tapies's work crossing over into calligraphy.