<Tr> <Th> Strunz classification </Th> <Td> 9. FA. 30 </Td> </Tr> <Tr> <Th> Crystal system </Th> <Td> Monoclinic </Td> </Tr> <Tr> <Th> Crystal class </Th> <Td> Prismatic (2 / m) (same H-M symbol) </Td> </Tr> <Tr> <Th> Space group </Th> <Td> C2 / m </Td> </Tr>

What kind of ions is orthoclase feldspar composed of