Is that not yours? peach/pink may work, no telling without seeing the actual space and surroundings.

The peach/pink color does match with the room very well. I can not tell if it will look strange to have the pink on the bottom and white on the top? No this is not mine but it is what mine will look like when it is done other than the color.

I would paint the entire surround white.

I just thought that would be so boring... Kinda like e1 has the same fireplaces in their house like all white kitchens everywhere.

If you don't want white, then pick a deep, dramatic color, but paint the entire surround the same. The woodwork is so nice, that it would stand out and be a focal point. Pinky-peach and white is going to be a bit meh.

It would depend what is going on with the rest of the room, but some suggestions would be Kendall Charcoal (HC-166), Newburyport Blue (HC-155), Newburg Green (HC-158), Glouster Sage (HC-100), or Wethersfield Moss (HC-110).

It would give this effect:

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I love a peachy pink but putting it with white and marble will IMO, make the room look very feminine. If that's what you're going for, go for it. If not, do a deeper color. Maybe you don't have white marble. Can you put up the shiplap, do a white primer on the trim and repost with your room?

What is the color palette for the room? Do you have furniture, rugs, art, etc? More pics of the room and the stuff already in the room would be helpful.

If you are doing white shiplap, then the FP surround should really be the same white.