Do you mean light, medium and dark shades of the same tile?

Or 3 colors of the same material/sheen tile?

Can we see the tile?

Yes, light, medium, and dark of the same tile. It is a linen look texture tile. The colors I am thinking about are Snow, Summer and Glow.

http://www.arizonatile.com/TOUCH-SERIES-P1007.aspx

Do not have samples yet. Hopefully getting them soon!

Snow = Off White
Summer = Beige
Glow = Darker Beige, but more Taupe

It will either look very relaxing or boring--hard to say without putting samples together. You might want to do a different mosaic just to add a new texture. I like how they used the glass mosaic in this Houzz photo. It's monochromatic, but you want to touch that mosaic.

If the matching tile works, your mosaic may benefit from a little touch of the dark color (Sunset). I have a sample of a similar linen tile with a sparkle. Very pretty for a bathroom! My tile colors look like Summer, Glow, and Sunset, and the accent tile combines the three shades (stacked pencil liners). The little pop of dark tile is very nice.

[Traditional Bathroom[(https://www.houzz.com/photos/traditional-bathroom-ideas-phbr1-bp~t_712~s_2107) by Thornhill Interior Designers & Decorators Avalon Interiors

Thanks may_flowers! I was thinking the same thing. Will look at the mosaics they have. I will surely find one I like ;-) I'm also thinking 12x12's would look better on the floor. The different size may add a slightly different look too.

Hi cat girl! Coming across this a year late but we are in the process of installing the same Arizona Tile in our master bath (combination of Summer, Glow and Sunset) and would love to see pictures of how your bathroom turned out!

I agree with the suggestion to add a mosaic accent strip for a little pop. I used 2 different colors of the same tile (Daltile's Continental Slate, in Brazilian green and Egyptian - so a very different look) with a stacked-slate/copper accent in between. The accent strip has colors from the other 2 tiles but has some shinier textures mixed in as well. Sorry I don't have any photos on hand, but I find it to be a very consistent, harmonic look. I think yours will look great!