Shirak is rich with tufa, pumice and limestone. The carbonate minerals form the rock types&colon; limestone, chalk, marble, travertine, tufa, and others. The surrounding lands near the city are rich in tufa, basalt and clay. Calcareous sinter is also called tufa, calcareous tufa, or calc-tufa. Other insulative plinth material might include lightweight stone like tufa or pumice. The forum is made of ashlar blocks of peperino tufa with Carrara marble. "Ridges" are massive toothy tufa ruins. Most tombstones are in the northern-most tufa formations. The buildings are constructed in travertine, brick, lime, pozzolana, and tufa. In the 6th c. BC temples were built in tufa, wood and terracotta. Some of the tufa covering the hillside was excavated to accommodate the bathhouses. There are two common forms of flowstones, tufa and travertine. Hotsprings and tufa mounds () are the largest of tufa mounds in Canada.