I believe that Dan y Graig No.4 Colliery is owned and operated by Three D's Mining Limited. This company has both UK and Hong Kong directors and so seems to have parallels to Riche Group, earlier owners of this colliery and of Johnson Mine at Blaenafon, which was Hong Kong based.
Dan y Graig No.4 Colliery spent a long while after reopening driving through old workings to reach a new block of coal west of the mine's previous workings. I believe that the mine is free-draining. I believe that the mine has been coaling for around two years and it employs a total of less than ten.
The licensed area is large. If anthracite prices hold up, this mine may have a long productive life as reserves are very large in relation to current output.