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Visual Arts

The mosaic will show images of the Nativity, the wedding feast at Cana, the Transfiguration and the Annunciation. (CNS)

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Installation of mosaic under way in dome of national shrine
January 9th, 2009
By Kaitlynn Riely, Catholic News Service

WASHINGTON (CNS) -- Nearly 100 feet above the marble floors of the Basilica of the National Shrine of the Immaculate Conception in Washington, a work of art is unfolding on a ceiling dome as workers install a mosaic composed of approximately 2.4 million tiles of colored glass.


Though their work is hidden from public view by an elaborate scaffolding structure, an ascent up an elevator, then up two sets of staircases, reveals a partially completed mosaic, named the Knights of Columbus Incarnation Dome.


The dome has been transformed from plain gray to a jigsaw puzzle of glass, composed of every imaginable shade of many colors.


Matteo Randi, an Italian who now lives in the United States, has been installing the pieces of the mosaic with other members of the Rugo Stone LLC installation team. As he walked around the scaffolding structure, he explained the process that preceded the installation of the mosaic.


In a shop in Italy, he said, the workers still use the original tools of the trade -- a “martellina,” or hammer, and a “tagliolo,” a wooden base with a sharp metal point.


The mosaicist uses the “martellina” to hit the piece of glass against the “tagliolo” to create the desired shape. He then arranges the tesserae -- the pieces of glass -- together to create an image. The mosaicist attaches the image to paper that has been coated with soluble flour glue. The mosaic is then cut into smaller sections so it can be shipped to its destination.


The mosaic was shipped via Federal Express from Italy to the United States. The 346 boxes arrived May 29, and the next day mosaic installers from Rugo Stone began the process of installing the mosaic.


Prior to the installation, the dome was crisscrossed with lines measuring the mosaic’s exact dimensions to map out the correct position for each piece. The mosaic was being installed through what the shrine’s archivist, Geraldine M. Rohling, called the “reverse mosaic method.”


The workers coat portions of the dome with cement, then remove the sections of tesserae and place them on the dome, with the paper side facing outward. After allowing a few hours for the tesserae to firm to the cement, they used water to remove the paper covering the mosaic and in doing so unveil a vibrant, colorful design.


Once it is completed, the mosaic will show images of the Nativity, the wedding feast at Cana, the Transfiguration and the Annunciation.


The mosaic installation represents another step in completing the vision of the original founders and architects of the shrine, said its rector, Msgr. Walter R. Rossi.


”Mosaic is timeless,” he told Catholic News Service. “Mosaic doesn’t fade.” Mosaics already adorn many of the shrine’s walls and ceilings.


The idea for the Incarnation Dome dates back to the 1950s, when the shrine’s iconography committee planned the artwork for the building, Msgr. Rossi said. The members of this committee planned for three domes to be decorated with mosaic art -- with the themes of the Redemption, the Incarnation, and the Trinity and Mary. The Redemption Dome was dedicated last fall.


The Knights of Columbus donated $1 million to the Incarnation mosaic creation and installation process. The total cost of the project will be approximately $3 million, Msgr. Rossi said.


In 2000, Msgr. Rossi’s predecessor, now-Bishop Michael J. Bransfield of Wheeling-Charleston, W.Va., gave different companies and artists the iconography committee’s original written descriptions for the domes’ designs. Artist Leandro Miguel Velasco was chosen to design the mosaic, under the direction of the Rambusch and Sons Decorating Co., located in New York.


Last November, after Velasco completed his design, the task of cutting the glass and putting the pieces together went to Travisanutto Mosaics of Spilimbergo, Italy. Msgr. Rossi visited the shop twice during the production period.


”It’s a time-consuming and tedious job which I wouldn’t want,” Msgr. Rossi said. “You need great patience.”


In the factory, about five people worked on the more difficult parts of the project -- like the faces and bodies of the people in the scenes. The more generic work, like the background, was done by people at another shop, he said. The most difficult part of the mosaic process, Msgr. Rossi said, seemed to be making sure men looked like men and women looked like women.


”You want to make them as real as possible, not cartoons,” he said.


Msgr. Rossi said he was pleased with the progress of the mosaic installation. Working six days a week in their first two weeks of work, the workers had already made substantial progress. The mosaic installation should be complete by July 10, Msgr. Rossi said.


In November, Archbishop Donald W. Wuerl of Washington will preside at a Mass to dedicate the dome. Msgr. Rossi hopes, tentatively, that the third dome will be completed in 2009.




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