Akro is my best guess at the moment. apologies for the poor quality, I hoped to get better photos but couldn't get them off my other phone. I can at least say that these photos are color accurate. some are taken in indirect sunlight, others taken using flash. the base (the white half, not actually sure if that is the base technically) is a very very faint blue, and becomes normal white in some spots near the patch. there is also a strip of yellowish tan on one end of the patch.
there are a few cracks and one chip on the marble, but they likely aren't visible in any of the photos. there is a "dent" visible in photos 7 and 8 at the seam. it is likely a manufacturing defect, though I'm not sure how likely that is on an Akro.
the marble is somewhere around 16mm or 17mm. All help is appreciated!