I have been reading up (believing it or not) on old glass and think this simple pattern was common on 1830's 1840's bit's of glass. It has a lot of wear to the base with a polished pontil, i'm not even sure what it's for as i keep coming across this size of dish and 9 times out of ten there described as sweet meat dishes or bon bon dishes, it was only ten pence so with the chip i thought it was worth asking the question here to see if i'm on the right track or not.
It's 41/2 inches in height, 4 1/2 inches across the rim and 3 1/2 inches across the base