Richard Long // Sea Lava Circles //Iceland // 1988
This work by British artist Richard Long is on loan from the Judd Foundation and was installed by Donald Judd at the Chinati Foundation on a concrete platform formerly used as a tennis court. The work was made in 1988 from volcanic rock collected by the artist in Iceland. It contains three equally spaced concentric circles of stones, each stone touching the next, with the largest circle measuring 13'7" in diameter.
http://www.richardlong.org/