Dennis, I *think* what you're seeing in the overhead blurry photos on the chip edges are not injection marks, but reflections of light off the curvature of the chips, and off the slightly scarred edges. That said, I do believe these are injection molded.
Here's an enhanced version (still cruddy!) of the seller's chip face photo:
I have a couple barrels of what I think are the same chips. Mine are what I think most people would call "grey", but they have a noticeable purple tint. Following are a couple photos of my grey chips next to some casino chips and an ivory colored dealer button for color reference. These are just quick iPad photos, but the color accuracy is pretty good.
In this first photo, you can see the whitish edges that these chips get from being scarred. On the chips that are face up, you can see the injection mold points as white dots on the chip faces (these are on one side of the chip only), which I rotated to the 12 o'clock position relative to the rack. The face up chip on the far lower right of the rack has had its edges cleaned up with 600 grit automotive wet-or-dry sandpaper, and it has been oiled.
Here's a close-up of the cleaned and oiled chip next to some Flamingos (again, with the injection mold point at 12 o'clock), in which you can see that the chip has a nice texture across the entire face:
• Nice texture
• Very flat (no warping in mine, anyway)
• Handle well
• Whitish scarred edges need to be cleaned up for best appearance
• A little lighter than Paulson clays, but they don't feel cheap (sorry, I don't have a scale)
I don't know who makes these chips, or how people value them, but I certainly think they're worth $50 for anyone who needs some blanks for fracs or a similar use, assuming one is willing to expend the effort to clean up the edges and oil them.
THIS is the picture I was referring to in pointing out the injection "pimples". I've owned super diamonds and while $50 is a good deal for that many chips, they are NOT clay. Just truth in advertising, as the ebay ad says CLAY. Other than that, fully agree with your Pro's and Con's for these chips. They'd be even better if they had a recess for a label to fit in... I had 1000 of these and 14,000 faux clays at one time. I'd say these were almost as good as faux clays (aka "casino dice"). I'd still take faux's over these.