what materials were used to sculpt it?
A form of hollow-cast concrete, reinforced with steel, which incorporated pebbles from the Potomac River.
Fountain of Time
 of a form of hollow-cast concrete, reinforced with steel. It was cast in a 4,500-piece mold, using of a material described as "concrete-like", which incorporated pebbles from the Potomac River.
what is fountain of time? It  is a sculpture by Lorado Taft where can you find that piece of work? In the Washington Park community area on Chicago's South Side which year did its sculpting first begin? May 1915
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Fountain of Time [SEP] Design and realization
The sculpture is made of a form of hollow-cast concrete, reinforced with steel. It was cast in a 4,500-piece mold, using of a material described as "concrete-like", which incorporated pebbles from the Potomac River. This composite material was an innovation at the time. For years, John Joseph Earley of Washington, DC, had used pebbles that seemed durable in the face of elements such as the weather and urban soot and grime. He had determined that by adding crushed pebbles he could create a new concrete mixture more durable than limestone but cheaper than marble or bronze. The reflection from the silica of the crushed stones complemented the durability with artistic beauty; the same material was used at Chicago's Fine Arts Building.