Thanks Grahami,
I wondered the map age,as there was no Adit or mention of level at the point of Rock View,but that is also the case in a lot of the BGS maps.
Doing a bit of Coal prospecting last year,we opened an old mine ,details we un-earthed,showed it last worked 1878,the faces when we eventually got that far in,were still on thier feet,the face posts still standing,and even a few pair of notched timbers on the roadways.
Yet there was no documented proof of the name of this Colliery,even though it was showed on the BGS map,with its Adits and access Tramways.