<P> The Smithsonian then radically changed the landscaping of the under - construction museum in summer 2013 . The original design for the museum planned a wetland with flowing creek, bridges, and native plants in this area . But cost considerations led the agency to completely eliminate it . At first, the Smithsonian proposed a low hedge . It brought this design to the Commission of Fine Arts in April 2013, which rejected it . The Commission expressed "great concern about the possible loss of the symbolic meaning that had been skillfully woven into the design of both the landscape and the building". In July, the Smithsonian replaced the hedge with a low dull black granite wall . The Commission of Fine Arts approved that redesign, and the Smithsonian brought it to the National Capital Planning Commission . As of August 2013, the NCPC was anticipated to approve it . </P> <P> Debate over the corona's finish continued into 2014 before being resolved . The Commission of Fine Arts repeatedly urged the architects to use bronze for the scrim, as it created a "shimmering, lustrous effect under many lighting conditions" and "conveyed dignity, permanence and beauty". Duranar paint was the first substitute proposed by the architects, but the commission members rejected it, noting that it had a "putty - like appearance under overcast conditions" and visually fell "far short of the beautiful poetic intention promised by the concept design". A second finish, the sprayable metal LuminOre, was rejected by the commission because it was difficult to produce in the high quality needed, and was prone to flaking and discoloration . Electroless plating and anodized aluminum were rejected because they lacked durability . A physical vapor deposition process involving a nickel - chrome plating was dismissed for not achieving the right color, luster, or warmth . In early 2014, tests were made with polyvinyl difluoride (PVDF). This coating was approved by the Commission of Fine Arts on February 20, 2014, and by the National Capital Planning Commission in April 2014 . </P> <P> The museum's groundbreaking ceremony took place on February 22, 2012 . President Barack Obama and museum director Bunch were among the speakers at the ceremony . Actress Phylicia Rashād was the Master of Ceremonies for the event, which also featured poetry and music performed by Denyce Graves, Thomas Hampson, and the Heritage Signature Chorale . </P> <P> Clark Construction Group, Smoot Construction, and H.J. Russell & Company won the contract to build the museum . The architectural firm of McKissack & McKissack (which was the first African American - owned architectural firm in the United States) provided project management services on behalf of the Smithsonian, and acted as liaison between the Smithsonian and public utilities and D.C. government agencies . </P>

When did they start building the african american museum