I hope you are finished with the stone, but just in case! This looks like insufficient prepolish.
1200 is much too coarse for CZ in my opinion. I suggest you step thru 3000 and then 8000 as the
final prepolish. Not only do you need to get rid of the scratches from the previous grit, but also
the stress fractures from previous grinds. CZ is hard and grinds very slowly on prepolish, best
polish is after an 8000 grit prepolish. It is hard to judge from a photograph without seeing the
actual stone.
I just finished a 18mm CZ stone and had very similar facet appearance even when 3000 looked good.
At 8000 it took forever to grind out those previous under lying blemishes. CZ can have various
directional hardness across the facets depending on what chemical makeup is used by the manufacturer.
Chuck G.