In chemistry the term stannate refers to compounds of tin (Sn). Stannic acid (Sn(OH)4), the formal precursor to stannates, does not exist and is actually a hydrate of SnO2. The term is also used in naming conventions as a suffix for example the hexachlorostannate ion is SnCl62−.
In materials science, two kinds of tin oxyanions are distinguished:
4 units (e.g. K4SnO4) or have a spinel structure (e.g. Mg2SnO4)
2SnO3 which may contain polymeric anions or may be sometimes better described as mixed oxides
These materials are semiconductors.
References
Stannate Wikipedia(Text) CC BY-SA