Grahamstown Potteries Drostdy ware embossed relief Stag Beer Jug

I was really excited to find this Jug in a Charity Shop this morning.  I have only seen one other in Wendy Gers “Scorched Earth” book. It is a well researched treasure of work on 100 years of south african potteries.  A must if you are a collector.  This jug has a mark on the lip.  Shown in the pictures.   I havent tried to get it off.   I dont know if it is just paint or it is covering a little damage.   I have decided not to try to remove it.  There is a chip under the glaze which must have been done in the factory.   Please dont hesitate to ask any questions.