<Tr> <Th> Mohs hardness </Th> <Th> Mineral </Th> <Th> Chemical formula </Th> </Tr> <Tr> <Td> </Td> <Td> Talc </Td> <Td> Mg Si O (OH) </Td> </Tr> <Tr> <Td> </Td> <Td> Gypsum </Td> <Td> CaSO 2H O </Td> </Tr> <Tr> <Td> </Td> <Td> Calcite </Td> <Td> CaCO </Td> </Tr>

What is not a main characteristic of minerals