Shanghaimon,
Thank you so much. This is just what I need to know in order to move forward. My tile just arrived this afternoon and I see what you mean about the uneven edges and the thickness. It is absolutely gorgeous and I do not want to make any mistakes now that I have gotten this far...almost there!
I have laid out several pieces. The tile man who came by earlier today to give me an estimate saw only the small 2x4 sample. ( tile had not arrived yet). He said I could go 1/8 or 3/16. Not sure he would say the same after seeing the larger tiles. He seems experienced but not sure if he has set this tile before.

Also, I would like to know if you used a grout color matching or contrasting
your debris series tile. My tile is Butter Toffee. Tile setter recommends matching tile.

Once again thanks so much for taking your time to help me out.
maxee

Maxee,

I would just have the tile guy go with the narrowest grout line possible, given the constraints of the uneven tile. It will still be much wider than you are used to seeing!

Because of those wide grout lines, I would *try* to match the color as closely as possible. You may not have any luck though, with the Butter Toffee. I wanted to match my tile (Cyclone with engobe, which is a deep gray with green-blue undertones) but there wasn't anything even remotely close from any grout company. So, we have a contrast. The design was complicated to lay out and had to fit EXACTLY, so that's another reason for the wide grout lines. It gives you some space to play with so that you don't have to make cuts.

Here is a pic of the tile:

Hi, Shanghaimom,
Your fireplace tile looks amazing. I love the design and the entire look. I now have a much better idea what to look for as far as grout lines and matching/blending color. Yours is an inspiration. It is stunning...I can't believe what a difference the design at the top portion makes. Very cool!
Thanks so much for sending this photo.
Maxee

When we laid out our backsplash (also fireclay debris), I felt that if you focus on a throughline rather than lining up one edge, you could get pretty small grout lines. But once I laid it out, I felt like the handmade nature of the tile really made a bigger impact if you had larger grout lines. Ours are 3/16".

And you should always put caulk, not grout, at any change in plane with tile...between the tile and the counter, for example.

[Contemporary Kitchen[(https://www.houzz.com/photos/contemporary-kitchen-ideas-phbr1-bp~t_709~s_2103)

Fireclay Debris tiles are so lovely. I would only offer one piece of advice. My Sonoma tiles are handmade-ish, so the edges, particularly the corners, are sometimes not perfectly flat. That can result in lippage. Ask me how I know. My subway backsplash is beautiful, until I turn on my UCLs. Lippage shadows are cast. It bothers me a lot, so I don't use my UCLs. Bummer. I think it could have been avoided with extreme care and probably slightly wider grout lines to even out the disparity. I think I might be able to mitigate the lippage shadows if I move my UCLs more forward, but that's a project for another day.