Name the structure of silicates in which three oxygen atoms of SiO44− are shared is

In sheet silicates , three out of four oxygen atoms of SiO4−4 unit are shared. Three oxygens of every tetrahedral are shared with others.In Pyrosilicates, three is only one shared oxygen in linear chain silicates two oxygen per tetrahedral are shared while in three dimensional silicates . All four oxygen atoms are shared