its not actually. it's a glacial erratic made from rock. but you would need to define wether it is sedimentary or volcanic. but probably volcanic.
nah, but it is in a field. boom boom. deffo not sedimentary. its been 13000years since it was dumped there. weather would of done for it by now.
How do we know its "a" rock? Unless its a monolith it's several contiguous rocks, a geological cluster. Someone will have to dig it up and have a look otherwise this thread is pointless.