DALLAS, TX.- Measuring more than 12 feet in diameter, Arnaldo Pomodoro’s massive Giroscopio I, 1986-87 is moving in more ways than one. Not only does the fascinating bronze and iron piece created by one of Italy’s most renowned avant-garde artists immediately capture the imagination, but portions of the sculpture also physically move.

Composed of external rings and two semicircular internal halves, the impressive sculpture – estimated at $400,000-$600,000 in Heritage Auctions’ Nov. 17 Modern & Contemporary Art Signature® Auction – resembles an early gyroscope writ large.

Thanks to Pomodoro’s expert engineering skills, the internal semicircles’ movement is made possible through the reverse rotation of the forms around a pin. This trick allows the observer to enjoy the revolving forms while standing perfectly still.

“We have an exceptional selection of quality sculptures in this sale,” says Frank Hettig, Heritage Auctions’ vice president of Modern & Contemporary Art. “As for Pomodoro, his sculptures are exhibited in prestigious museums, private collections and public spaces around the globe, and the piece we have coming up in our fall sale offers a chance to own a rare work by one of the world’s most significant contemporary artists.”

In addition to the Pomodoro piece, the sale offers another large-scale work: Plaque Eiffel, 1989 by César (estimate: $150,000-$250,000). The welded bronze sculpture stands more than 9 feet tall and pays homage to the Eiffel Tower, whose 100th anniversary was the same year as the work’s creation.

The November auction also has two works by Tom Otterness, one of America’s most celebrated public artists. The first, known simply as Bear, 1998 (estimate: $80,000-$120,000), is a whimsical bronze sculpture depicting a downcast bear that looks like he could use a hug – and a new home.

The second Otterness sculpture, Rebellion to Tyrants, 2000 (estimate: $20,000-$30,000), also crafted from bronze, stays true to its title by featuring two small figures toppling a large one. The bigger figure, clutching a stuffed money bag, sits atop a tall structure, gazing down uncertainly at the ground below as the smaller figures work to overturn his building.

Maquette for Sky Landscape I (A), 1976-1979 (estimate: $60,000-$80,000) by Louise Nevelson is the auction’s only sculpture by a female artist. The striking piece made of welded steel painted black is arresting not only for its stark monochromatic palette, but also for its unexpected combination of sharp angles and contrasting curves.

Nevelson became famous for her found-object sculptures in the early 1940s, but by the 1960s she was beginning to experiment with other materials, including plastic and metal. Today Nevelson’s sculptures are featured at several notable landmarks, including the United States Courthouse in Philadelphia.

“Pieces by female artists are in high demand right now,” Hettig says. “The most serious female artists of the 1950s through the 1980s are finally getting their due.”

Other sculptures in the sale include:

• Mariposas, 2008 ($60,000-$80,000) by Spanish artist Manolo Valdés, an eye-catching bronze bust sporting a headdress of fluttering butterflies

• Virginia Sentada con Ropaje, 1977 ($20,000-$30,000) by Francisco Zuñiga, a bronze sculpture depicting a robed woman lost in thought; the piece is signed and numbered by the famed Latin American artist

• Stainless Piece L, 1974-75 ($15,000-$25,000) by British artist Anthony Caro, a stainless-steel sculpture made of geometric forms layered on top of each other