Twelfth and Callowhill is Post-Industrial Central. Warehouses, idle factories, and storage facilities mingle with renovated lofts and a few art spaces. Sometimes it's hard to tell the art from the industrial cast-offs.

A recent walk around the neighborhood found passersby doing a double-take upon approaching a large translucent cube with flotsam and jetsam suspended inside. A quick Google revealed the person responsible for its creation, Japanese-born Philadelphia artist Keiko Miyamori. The sculpture, City Root, has had a strange journey, and it's not over yet.

As an idea on paper, City Root won a 2004 art competition held by the Frederik Meijer Gardens & Sculpture Park in Grand Rapids, Mich., and so Miyamori set out to realize it. She spent $100,000 on the basic material, a UV-resistant crystal-clear resin. A mold was fabricated in Allentown. The "pour" was made in Easton. The piece was then shipped back to Allentown to be taken out of the mold and polished.

It was shown in Philadelphia and Pittsburgh, and eventually was shipped to its commissioner in Grand Rapids.

It's a striking and thoughtful work that explores the relationship between city and nature. Miyamori froze in the resin a 4,000-pound root mass of an oak tree pulled from the ground at 11th and Girard, where the Cambridge Plaza housing project was coming down. Bricks, glass, and metal were entangled in the root, and they have been preserved in the blood-red cube along with the root.

But during the curing process, cracks began to appear in the work, leading the commissioner to reject the final product.

"I told them that the cracks added more value in my sculpture because it expressed my original concept: 'power of nature,' " Miyamori said yesterday.

But the Meijer didn't buy that argument, she said, so City Root was sent back to Philadelphia. Bruce Shelly, owner of Shelly Electric Co. at 12th and Callowhill, agreed to let it remain on the property for three years.

"If I cannot find an opportunity to sell it, the sculpture will belong to him automatically," the artist says.

Miyamori says she spent $170,000 on the project, only $95,000 of which was covered. So she's left holding the bag on the rest unless the piece sells. And that $170,000 did not include any payment to the artist for her time and labor, she said.

"I had to absorb the rest and had to work like crazy these years. I don't have children, though I think I have the feeling to be a parent," she said of her creation. "I had to look after her without paying until she graduates school - hoping that she will be independent from me and create her own reputation to earn money by herself."

Joseph Becherer, curator of sculpture and director of exhibitions for the Frederik Meijer Gardens & Sculpture Park, would only confirm that Miyamori won the competition and that City Root was not now in the collection, but would not comment further.

In the meantime, there it sits behind a chain-link fence, like Prometheus bound. Seven-by-six-by-seven feet cubed. Seventeen thousand pounds. Waiting for a home.