How do you tell the grit of a barber hone?

Posted this question in someone elses thread. Thought I would try it on it's own.
Can someone please explain how to tell the grit of a barber hone. Can it be done with a glass? Is feel accurate? I know that the barber hones were made in many different grits. Did the barber buy a particular grit stone or did he use what ever he had at the time. I have read that in the old days many of the barber hones had the manufacturers name on the stone. Perhaps they were given to the barbers as a promo? Did the barber care what grit he was given, if that in fact was the case?

I'm afraid that experience is the answer.... sort of. Once you've used enough stones you'll be able to say " this leaves a finer finish than the 8000 but not as fine as my shapton pro 12k.... so... we'll call it a 10 k." The problem with this is that you need to use a bunch of stones before you can ballpark guess it like that.

Plus, the fact that manufacturers don't have an industry standard that is globally adhered to makes it hard to say. Example :the Norton 8k is 3 micron, whereas the Shapton glass 8k is ~1.9 or so. It's hard to say exactly what an "8k" is....

Some barber hones are finer than others, some coarser.

Back in the old days a manufacturers name in the hone was a cheap way to advertise and build brand loyalty/recognition.

You've entered the murky waters, my friend. I'm sorry that there isn't much of a definitive answer on this question (and many others that are asked at SRP). I WISH I could say that there was something more concrete, but there just isn't, AFAIK.