This kitchen floor is a 16x16" vinyl tile by Armstrong. It's their Alterna Durango series, the color is Buff. It does a brilliant job of looking like natural stone tile, but is so much easier on the feet and legs. Very durable, as well.
Thank you for the question.

Great question about what type of flooring was used in this picture. I love the large vinyl tiling in this smaller kitchen. The marbled colors look amazing with the darker cabinets and light colored counter-top. My husband and I are hoping to install new flooring in our kitchen this next spring. I'd love to do something like this. http://www.vogelscarpet.com/all-luxury-vinyl-flooring