The Lister black stone is a honing stone I received with a batch of Zulu Grey stones we purchased. I received them as 'Leister' stones, but have no furter detail on them, so I simply dubbed them 'Lister' as not to create any expectations to buy Welsh slate, Black Arkansas, 'Black magic' or any other well known and discussed whetstone. What I can say is that it is not the same as the local slate I have been experimenting with, it is more solid in colour and have little deviations in terms of grain and patterning, and looks very uniform and stable.
I know we can never put a 'grit' value down to natural stones, but if I had to I'd say it feels much like my 8k Norton stone, the stone is fine and smooth. I spent about 15 minutes on a Gold Dollar razor and got some great popping of the hair on my arms, so it does the job of a honing stone for sure, we just need to find its place in your progression.
For the time being we'll offer it as a mid range to high end range natural slate stone, something I'd probably use before my 12k Naniwa or 13k Sigma. The verdict on them is still out until I have had time to use them some more. What I can also add is that they are a lot smoother than most black vintage stones I have come across, so it is certainly not a stone that was/is commonly found in SA.
There are only a few of these available and I doubt that there will be more, we offer them at a price we deem fair, but may increase/decrease the rate as we get to know the few we have, so you are buying at own peril. a Bit of a gamble on this one, who is game?
Found in the wild. Size 220x56x20mm. They weigh around 820 grams a pop.