This can be done several ways. One is like you said with a track system top and bottom, but if you notice on the enlarged photos in the link there is no track on the counter. If I was detailing this out I would have the counter extend into the spice rack area and install a small metal post, detail a groove in the bottom of the slab that is to slide, and use a sliding door system similar to this (http://www.pchenderson.com/sliding_door_gear_product.php?category=Commercial&config=Straight+Sliding&range=Straight+Sliding&id=168). This will allow the sliding door to be attached at the top only, and have a "guide" with the post inside the carved channel of the marble door. Also the recessed door pull looks like it came from Hafele (http://www.hafele.com/us/index.htm)
Jason Van Noord
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