Cerium Oxide is the abrasive used in/on the Trizact pads.
Trizact was used by Brunswick when they first made particle balls in the late 1990s. It was the only abrasive hard enough to affect the particles used by Brunswick. This is one reason they lasted so long, with some people using them effectively to this day.
I recently used the white pad, their finest, smoothest pad, over a 4000 grit Abralon pad on my Columbia Blue Dot. While it can still hook, the amount it does hook has been reduced greatly.
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