Chris Mcloughlin said this coin is a very recent find. He had identified it as a voided short cross penny of John but asked if this was correct and he also wanted a valuation.
Firstly, this is a class 5b penny of King John. On the reverse the legend reads +GOLDWINE ON CA, so Goldwine is the moneyer and Canterbury the mint.
The legend is a bit weak on both sides and the coin is dark in colour but it is otherwise in about VF condition. To a collector it should be worth around £100.