Ralph, thank you so much for your reply.  

Here is what I can  tell you.  I have multiple references (for example, 
inventories of 18th  century tool merchants) with specific reference to Turkey 
Stones.  The  Rees' in their editing of Christopher Gabriel's papers point 
out that these  stones were the pinnacle of sharpening stones.  Eighteenth 
and early 19th  century references also point to Turkey Stones or Turkey 
Oilstones as being the  best.  When Arkansas stones were discovered in the 19th 
century, Turkey  Oilstones were still considered better.

Internet searches indicate these  stones (either white or black) were 
quarried (or shipped from) the Smyrna  area.  A quote from Holtzappel's book 
illustrates:

The Turkey  Oilstone can hardly be considered as a hone slate, having 
nothing of a lamellar  or schistose appearance. As a whetstone, it surpasses 
every other known  substance, and possesses, in an eminent degree, the property 
of abrading the  hardest steel, and is at the same time of so compact and 
close a nature, as to  resist the pressure necessary for sharpening a graver, 
or other small instrument  of that description. Little more is known of its 
natural history than that it is  found in the interior of Asia Minor, and 
brought down to Smyrna for sale. The  white and black varieties of Turkey 
oilstone, differ but little in their general  characters, the black is, however,
 
somewhat harder, and is imported in larger  pieces than the white.

Apart from some information on chemical/physical  composition, that's what 
I can tell you about what I am trying to find.  I  don't really know when 
they stopped being a commercial item in the west. I don't  know if these kinds 
of sharpening stones are available in Turkey, but that's my  last best 
hope.  

I figured that if I could tap into the Turkish  Galoot Society, I'd come 
closer to finding out if obtaining these stones is  possible.  I have written 
to the Turkish Ambassador in Washington, and to a  Turkish cultural office 
to see if I can get in contact with woodworkers or if I  can obtain a source. 
 I've also written to a Turkish firm that sells hand  tools to see what I 
can learn from them.

Cheers,
John

John M. Johnston
There is a fine line between hobby and mental  illness. Dave Barry
 
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