Breche Violette marble from Italy. In the rotunda, the giant columns in the four open spaces are made from Minnesota granite. The deep bronze columns on the north and south were quarried near Ortonville, Minnesota and the purplish gray columns on the east and west were quarried near Rockville, Minnesota. Dividing the statuary niches and the Kasota stone walls in the rotunda from the "Civilization of the Northwest" murals above them is a line of Sioux Quartzite from a quarry in Jasper, Minnesota. Previously it was thought to be Catlinite/Pipestone, which is prized by Native Americans, primarily those of the Plains nations for use in making ceremonial pipes. During the 2013-2017 renovation, the stone was tested and found not to be Catlinite. Artwork The State Capitol opened in 1905 with roughly 60 artworks that totaled $300,000, or 7% of the $4.5-million project budget. Over the years, more art has been added to the Capitol, totaling nearly 150 pieces in 2017. Gilbert sought out many of the finest artists of the period, such as Kenyon Cox, Elmer Garnsey, Edwin Howland Blashfield, Henry Oliver Walker, Edward Emerson Simmons, John La Farge, Douglas Volk, Francis D. Millet, Howard Pyle, and Rufus Fairchild Zogbaum. Much of the original art is allegorical. Gilbert's trips to Europe encouraged his ideas, but he was more directly influenced by the 1893 World's Columbian Exposition in Chicago. In particular, the inspiration for the Minnesota quadriga, a group of figures entitled Progress of the State, was the Columbus Quadriga, a statue depicting Christopher Columbus standing in a four horse chariot guided by two maidens carrying staffs of victory, that Daniel Chester French and Edward Clark Potter had modeled for the World's Columbian Exposition of 1893 in Chicago. Gilbert saw this quadriga group at and made plans to have artists adapt it for Minnesota. As work continued on the interior, multiple groups, notably American Civil War veterans, the Minnesota Historical Society, and some politicians, demanded that the artwork in the Capitol illustrate historic events of Minnesota’s past. The current ornate look of the Governors Reception Room was partly a response to Minnesotans' suggestions for pictures from their own history which gave Gilbert the opportunity to upscale his plans for the room and to include six large paintings that span 200 years of the area's history. In 1944, the custom of displaying governors' portraits in the public corridors was initiated. In 1971,