They are quite slippery, and pretty unstable in stacks.
The NexGen Pro chips are 9.0g injection-molded abs plastic and are a much more durable chip than china clays, but they also lack the material components that provide 'clay-like' characteristics (feel and sound). The mold actually copied the Palm Gaming interlocking reverse-L greek key mold, after PGI and their original Chinese manufacturer parted ways. They were sold with various label designs and as blanks, and used a interlocking reverse-J mold greek key style with 4D14 spots, emulating the style used by Paulson on their Classics line (and others). The Progen 80 chips are 10g injection-molded china clay, and are generally considered to be near the bottom of the barrel quality-wise when compared to other china clay chip offerings.
