On May 1, 8:57*am, wrote:
I can barely feel the sctrach with my fingernail but it is visible.

I tried using a random orbit car polisher and red rubbing compound.

No joy.

Any suggestions?

Any polishing will leave a dip in the surface which may or may not be
acceptable if viewed in certain lights. One other option is to modify
DadiOH's technique and do the entire surface to a matte finish to mask
blemishes. Or, replace the slab with a new one. Your call.

Joe