well it is caithness as Allan Scott said below
I showed the pictures to Helen and Gordon and they confirm that it is a Caithness piece.The DG above the CG stands for Douglas Cowie.. Cithness Glass.Douglas worked for us from the late 70s to the late 80s.Gordon thinks that the piece dates from the early 80s.the design is a sandblasted stencil.They think the vase was a design sample that never got issued.How it got on the market,who knows?.I would imagine a lot of things found their way out of the Wick factory on their own steam,especially when it was closing down.We are still puzzled by the CoG mark,none of us remember it being used ,so we think it must be something Douglas used for his own information.It might of been for the design or something.I hope this helps you somewhat.