Couple more pics

People can't help you in a vacuum! This choice relates to other elements in the room and adjoining spaces and you haven't shown us those.

Here are some pics of the space. Any suggestions welcome!

I think first one is best, second least favorite too much brown in room

The white tile seems overwhelming.

Agreed. As much as we like the copper tile, it adds too much brown to the space. The white is overwhelming. If none of the four samples we picked up make sense, any other suggestions??

Bump

How about going all out and using stainless steel?

In this case, I would remove the black trim, cover the wall with stainless steel then add a narrower polished chrome trim.

Thanks for the picture. That's really bold, it feels like too much metal

You could go with a large porcelain tile in one of the mid tone colors of your back splash. Or maybe a natural stone (look alike?). I always find good ideas on the Tilebar site. They have pictures of a number of contemporary fireplaces that might resonate with you. For a streamlined look you could try a slab of granite or quartz or quartzite from the remnant pile at your marble fabricators. Good luck!

Lets talk about not cutting that wall up anymore with tile below the mantel, there is already a lot going on here so I would tile the whole thing to keep it congruent.

Agree with doing it ALL the same and the first one is the best. You will regret a huge dark wall.

What about getting a similar tile to the white in a light beige/cream color. It’ll blend with your warm tones. Something that matches Your wall color and just adds texture. It’ll be more calming to your space/eyes.