Thuringian?

[wdwrx]

This is a hone I picked up at an antique fair a few weeks ago. I'm pretty sure it's a Thuringian, but I'd sure appreciate it if you all jumped in with your opinions. I noticed an earlier thread with lots of Eschers in it, and I thought that mine looked an awful lot like some of the grey or green stones.
It's got just the faintest lines of blue running through it, thicker and heavier on the back side.

It seems almost buttery smooth, and cuts fairly quickly with a slurry. I've been starting with a fairly thick slurry like the pic, and watering it down a bit every 20 or 30 laps until I'm using clear water. Then maybe another 50 laps.
I've always gone next to the Nani12K and then Spydee UF, but last week I was starting to get the idea that the edge I was getting off this stone was sharper than I thought, so last night I decided to try taking it as far as I could, and not go to any other hones.

I tried holding it in my hand, a step forward for me, and seemed to find a sweet spot where the razor was just hovering over the hone... hard to describe, but it felt as smooth and light as a whisper on the hone. Arm hair seemed to just fall over at the sight of the edge.

The HHT test was a little funny though.... It seemed to fail miserably, sometimes, but when it passed, it passed without a speck of noise or resistance. Unlike any other edge I've managed to get yet. I can do a HHT 3 or more often, 4 after stropping pretty consistantley, but this one is weird. I read it as either a HHT 0 or a HHT 5, but nothing in the middle.

I'm going to try that razor out tonight, and see how it shaves.

These are some pics of the hone. ( I made 'em big to show as much detail as I could..) I think the color changed a bit somewhere, there is a bit more green to the stone than shows. The faint blue lines show, the back side seems almost mottled in places. It's been wetted down to show the color better. I've also shown some slurry. It's almost milky white, and that's about as thick as I use. Does that seem right?

So, makin' a long story short: IS it a Thurry? And does my slurry look OK, should it be thicker, or thinner? And what's up with the HHT? Why such differing results?