the tile setter will have to build up the portions where the glass will sit. for the border frame, do either a liner of some sort in the same glass or the marble.

can I see a picture of both tiles and the kitchen?

No? Use one tile. Sounds like very unnecessary over kill. Pick one tile and if you are worring about marble behind the cook, simply use the glass. Everywhere. If it's "perfect" it's perfect for the whole shebang. Hard to say without pictures of all and the COUNTER tops.

NO NO NO to a fancy thing wall behind the stove that IMO only works in a huge tuscan style kitchen and even there I think it really does not make sense. A simple backsplash that goes everywhere is a nice clean look and then add some accessories if you want .

Is your glass mosaic a linear pattern? Do you have photos? If you are setting the mosaic vertically, it may look better covering the whole stove area in stead of a framed section. Post some photos and we can help you out.

I had to do some clean up first before sending pics! Still hanging lights and reloading the cabinets with dishes etc so the kitchen was quite the mess. Here is a view of the kitchen, the marble tile we want to use on most the area, then the glass feature over the stove. I think the glass will be too busy to use everywhere, but wanted a "pop" of it over the stove. There will only be paint over the hood of the oven that still needs to be done, but the rest will be tiled

The two tiles together on the wall. There will be a pot filler also added.

This is what I want to frame above the stove.

Photos help a lot; beautiful kitchen, but I think the selected tiles are not right for the space. The mosaic is too contemporary to the style of the kitchen and the marble may be too "cool" for the rest of the colors.

Thanks for the feedback. I hate that I REALLY like that glass tile and the colors with the cabinets, but I do see what all of you are saying. The last thing I want to do is take away from the cabinets and countertops, and they all be in competition with one another. So, do you think I should consider a basic white tile? Or is that too cool? Or could I consider a thin band of the glass tile around the kitchen (horizontally) with the subway tile? I did that with our house in IL four years ago and really liked that. I'm feeling quite lost/overwhelmed with this part of the project!

no band, no design. I didn't know you had an already busy looking kitchen which is why I asked for pics.

sorry, those glass tiles, nor the ss mosaic, do not work. the stone is beautiful. let that take center stage and the tile the supporting role. if you want a pattern, try a herringbone w/larger subway tiles. I'd pick a color in the stone. not so much a bright white,,,maybe a vanilla or cream?

if you want a darker glass,,

Wow Beth- that is so cool that you were able to put that in our kitchen pics! Thank you! I do appreciate all of the comments here and you've all taken me to the "other side" and I've given up on the tile glass that I loved so much! I'm leaning toward a cream or light tan stone looking tile (more rustic than contemporary) and just have straight tile. I do love herringbone look, but I'm really feeling like my tile needs to compliment the kitchen, and not try to steal the show!

if you want more of handmade type of tile,,more rustic, you could try CleTiles or Fireclaytiles.

unless you want something like these, more of the wavy, look

another one is the fire glazed brick. you know, they make this in black. would look stunning next to your cabs/counter

you could do more of a creamier grout, not bright white

here is a white so you can see how it looks.

the other option for a matte dark,, is basalt or black slate

Good timing on this topic for me, as we are in the middle of a new house build. Hubby just asked me about what are we going to do in the kitchen.. as there is maybe 4 inches under the windows/trim and what should we use ... are we even going to be able to put a bs there?? will need to look carefully at this as on left side of window/trim there will a the fridge and on the right side, the corner cooktop.. sigh lots to think on

Thank you so much Beth! I really like the fire glazed brick, but I'm leaning to the lighter color that looks cream to me. I don't want white. Needs to be softer/warmer.

CleTile has these, in this creamy color. they are $3 each ($18 sf) and are 2.5X8". that's a good size.

this is a mock up I did for another OP using that tile in Parchment:

Arizona Tile has these in a porcelain glazed

and fireclay tile makes these in beautiful tiles.theres a link here on Houzz

https://www.houzz.com/projects/421323/our-glazed-thin-brick

I do like these in Andromeda! It would really look stunning against your cabs

lots of different shades to choose from in these and their hand made ceramic tiles. they have about a dozen light creamy shades. check those out as well.

https://www.fireclaytile.com/subway-tile/colors/

Just buy quarter round that matches your carrera tile. Should blend in just fine.

UMMM. Depending on the BTU output from the gas range, you may need a stainless back guard.

If it is not a high output BTU range, I would go with plain tiles so that the counter top remains the star of the kitchen.