It appears that the tiles are marble. Do you know what type of grout was used?

Maypei warm grey

Okay so here’s an update, my contractor tried using Meipei grout refresh in a darker color, overall it looks better but there are parts where it looks faded. What went wrong?

Okay so here’s an update, my contractor tried using Meipei grout refresh in a darker color, overall it looks better but there are parks where it looks faded. What went wrong?

I used Mapei Warm Gray for my new Carrara shower and freestanding tub surround - it looks perfect. I did a lot of research before selecting that specific grout and color. However, my marble has a much lighter/whiter background than your floor tile.

Personally, I think your floor looked nicer with your initial grout color. Sorry.

However, I wasn't asking about the color - I was asking about what type of grout. For example, if Mapei FlexColor CQ was used, you can add a different color grout over the current grout instead of coloring it because the grout will stick to itself even after dry. (you could remove just a tiny bit if needed in order to have enough room for the new grout). Other types of grout require at least 2/3 removal of the current grout before adding new grout.