Contractor was the designer.

What does the contractor suggest as a fix? They make tile trim but that needed to be accounted for before installation.

He says there is no solution. Would’ve a tile edge trim worked here?

Have a solid surface fabricator make up several feet of color matched trim with a returned end and install it over the tile.

This guy’s never heard of Schluter strips? Jeez.

I'm sure too late now, but perhaps for the next person - I agree on the Schluter edging. I don't have a window but this is what they used on the edge of the niche (3 sides, mitered) with quartz on the bottom and tile on the other 3 sides.

Your tile is beautfil by the way! What exactly did you use?

"This guy’s never heard of Schluter strips? Jeez. "

Probably not a good idea to criticize someone's lack of knowledge while demonstrating your own:)

Schluter is a company. Not a product. Sadly, many folks on Houzz absorb marketing instead of product knowledge.

The product is Tile Profile Trim. With many manufacturers lines available throughout the states.

Blanke Corp.

https://www.blankecorp.com/

Progress Profiles

https://www.progressprofiles.com/en/profiles-for-floors

Profilitec

https://www.profilitec.com/en/products/floor-covering-profiles

Custom

https://www.custombuildingproducts.com/media/60093375/profiles_brochure_proplb_5_14_web.pdf

MD

http://mdbuildingproducts.com/product-category/flooring-products/ceramic-tile-trims/

Dural

https://www.tileshop.com/finishing-pieces/accessories/dural-metal-profiles

Schluter

https://www.schluter.com/schluter-us/en_US/Profiles/c/P

Litokol

https://www.litokol.it/en/10-metal-tile-trims-and-skirtings

Kuberit USA

https://www.kuberitusa.com/

and more.

OP go with Joe C's suggestion.

Seosmp- thank you. The tile I picked was called EC Grayish, 24x48 polished porcelain tile.

Thanks Creative Tile Eastern - my understanding is it’s too late for the tile profile trim. It was supposed to be installed when the tile was being laid down?

That's why his last line was " OP go with Joe C's suggestion. "