Cleaning The Merchandise Mart's Epic "Merchandise Around the World" Mural

The Merchandise Mart, towering 25 stories at its highest point and occupying four million square feet, rests along the Chicago River as the epicenter of downtown Chicago life, culture, media, and business. Finished in 1930 and massive in its construction, The Mart serves as a monument to early 20th-century merchandising and architecture. Even after more than 80 years, this Art Deco landmark continues to be a leading retailing and wholesale destination, attracting people from all over the world.

The Merchandise Mart’s lavish entrance faces the water and features a 17-panel mural that is “a panorama of the world’s commerce and industry.” Titled Merchandise Around the World (1930) and created by Jules Guerin (1866–1946), the mural is visible between square marble pillars that form a colonnade in the main atrium. Guerin collaborated with the architecture firm Graham, Anderson, Probst & White for the commission of the Merchandise Mart’s mural series.  The panels are delicately colored in rose, green, brown, and cream with metal leaf background details. Each panel is a market scene from a different country: Turkish rugs and textiles being sold in a bazaar next to a mosque; silk and pottery markets near Japan’s Mount Fuji; sleighs carrying furs in Russia, commercial ships in Germany, a caravan of camels carrying Egyptian cotton pass a pyramid; and merchants selling their wares in Switzerland. Merchandise Around the World serves as a welcome to more than 38,000 visitors and tenants passing through the lobby every day.

Jules Guerin is one of America’s most important muralists of the 20th century. His most famous works include those at Pennsylvania Station in New York, the Lincoln Memorial in Washington, The Continental Bank in Chicago, and The Chicago Civic Opera. Guerin is also known for his drawings of Daniel Burnham and Edward Benne’s Plan of Chicago in 1907. These drawings are spectacularly colored, bird’s eye perspectives for a proposal of the city of Chicago.

As you can imagine, over the past eight decades, an immense amount of foot traffic has passed through The Mart’s lobby. This being said, the murals needed quite the cleaning. Last conserved in 1991 by The Conservation Center's staff, Guerin’s masterpiece has since accumulated heavy grime, with its varnish significantly discoloring. “Humans create so much dust, especially with the amount of people coming in and out of The Mart on a daily basis,” said Amber Smith, The Conservation Center’s Senior Painting Conservator and project manager for The Mart’s murals. “Another culprit is the air ventilation system—when they blow directly onto the paintings everyday, dust is bound to stick to ones with thicker varnish.” Amber and her team’s primary goal was to remove the grime and the varnish from the mural, then apply a fresh coat of varnish, to bring Merchandise Around the World back to its intended glory.

The grime was first eliminated with cotton swabs dipped in an aqueous solution, followed by organic solvents to remove the varnish. Amber elaborates: “Each cotton swab—measuring two-inches tall by half inch wide—took care of a 3" x 3" square surface. We clean in shapes of the composition so there are no hard lines. Most surface areas took several swabs to clean. During the first swab you get the majority of the grime off; and then you go back with a second or third swab to remove all residual grime. You repeat this process until the swab comes away clean.”

Conserving a historic, 17-panel mural in an internationally recognized building comes with its own set of unique challenges. First, due to the plaza’s grueling workday schedule, Amber and her team were allowed to work only during off-hours, meaning 6:00pm–2:00am. “My sleep schedule had to be adjusted a little,” Amber said. Standing on a scissor lift for eight hours per night, plus swabbing repetitively with a small stick of cotton on a very large surface also makes the work seem endless at times. “Some panels cleaned relatively easily, while other panels were tougher to get the grime off. But once you run numerous tests with a couple of them and figure out what the commonalities are, you get into a groove.”

This entire process took a team of four conservation technicians (including Amber), working for more than 630 hours and going through at least 35 large rolls of cotton. Needless to say, this was a labor-intensive, but very satisfying project for The Conservation Center. “We’re proud to have put forth lots of love and care for The Mart’s murals,” said Amber. “Once the panels were all cleaned as a whole, the lobby immediately became brighter. It's a good feeling to know that we tackled all 17 murals—it's a huge accomplishment. We hope the thousands of visitors walking day in and day out of the Merchandise Mart will once again appreciate Guerin’s masterpiece for Chicago.”