Hi they look like they are marble and possibly from Ca Pietra. http://www.capietra.com/shop/stone-walls-floors/jet-set-collection-milan/.  Happy hunting!

Hello, Have you seen our Basalt Porcelain & Basalt Grey Porcelain? We are happy to send free samples to you so please do get in touch if you would like to receive some. Please contact enquiries@floorsofstone.com with your details and we can arrange this for you. I hope this helps. Molly // Floors of Stone

These are the tile samples I have so far. On the left - small top dark grey, under that is a tile with faux stepped marble effect tiles that are more slate toned. Large tile to the right is the mandarin stone one (v expensive, lol) The walnut in the middle I love the pattern but it’s not as rich a colour as I wanted and I can’t find anything else online in an American walnut style tile. The bottom tile is a v v pale grey with similar pattern to the mandarin stone one. How would you work these tiles together? Walnut floor and sink unit and dark grey all over the walls? Just the patterned grey on the back of the shower wall and sink area and plain grey on other walls?? :0/

That's interesting colourhappy - we did omit the aqua tiles and put just the taupe with blanco (which has some grey tones in the variations) but it looked a little bland which is why we thought the aqua might liven it up but now I'm thinking you are right and they are too cool for the flagstones.