Stone Coarseness?

I have acquired 3 old stone recently and was hoping to glean some information about then from this treasure trove of a forum. Two I inherited from my father. He used them occasionally in his wood shop some 30 years ago. He advised me to keep both stored in water and so i have been. The last I picked up at an antique store. Are these anything special? Worthless? Should they be used/maintained/stored in any special fashion?

All i know about these blades is below if anyone can add something, thank you.

Below is the larger of the two and I think I have its basics worked out. Marked King then some characters then #800. I assume thats 800 grit? k? Following based on almost no experience with stones......It feels fairly soft when I use it. Builds up just a tiny slurry slowly.
Attachment 172208

Next is smaller and much thinner. I would expect it to be a much finer stone. No experience....feels very very soft and seems to build a slurry fast.
Attachment 172209

Last i picked up at an antique store. I store dry. Very hard. Very smooth. No slurry. I've done some research but no info on coarseness. Heard some people say its a good finishing stone.
Reads : Emerald Razor Hone;... Pike Manufacturing Co;... Pike NH USA...
Attachment 172210

I have managed to put edges on razors and shave with them. The result was not nearly as good as my pro honed but not painful either. Last attempt i went in the order posted. I can get a good shot of my edges.

Wondering if I can infer a coarseness of a stone based on its scratch pattern?

One of my first real honing attempts. Before: no bevel/minor pitting/rust/staining...not sharp
After honing below
Attachment 172211


Still a couple stones and a lot of experience away from how my pro edge looks but it cut hairs off my face.

My guess is that Modine will have some info about your Emerald Barber Hone. Give him a chance to respond.

The size looks a little odd but I agree with Iceni that it does look rather similar to the King 6K. Might be worth going back and forth between the second stone & the barber hone to determine which is finer. A little chromium oxide or other fine abrasive on leather, balsa or something similar could be a cheap and easy way to max out the edge.