I also want to warn you that marble flooring is subject to etching and staining, Unless this is a household of only adults, you can expect that little boys will miss the commode at times, and their urine will etch the marble and stain it. I loved marble tile, too, but got real when I thought about the idea of some future elderly dog deciding to pee on the bathroom rug and ruining my floor. Not worth it!
You can find marble-look porcelain, even in interesting patterns. I loved this one from Wayfair's AllModern.com
Carrara-look porcelain Hex in 7 x 8 inch tiles. You can play with the pattern to either do a 3-D effect like tumbling blocks, or you can put the dark and light sides together to make triangle patterns in the flooring. Check out the various pictures on the left of the page.
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