Where are you wanting to put the cutains there is no way to get an answer with no more info.

I don't see the point of curtains with the stained glass? Can't see that curtains would compliment the glass panels/ vice versa.

Also, I would hang the panels inside the window frame instead of outside as they are now. Would use clear heavy fishing line to suspend them and paint the eye bolts or cup hooks white to help them disappear.

Then, maybe some light sheer curtains if you must hang curtains but better without, IMO.

The curtains are for other windows in the room not for the windows where the stained glass is hanging

Pictures of rest of room would be required to make a suggestion plus the window(s) you are talking about.

So much happening....I would clear that mantel off and start with very little. The stained glass is the star. Brown Dog is right about the hanging of them.

Yes, use small tea cup hooks to hang the panels and center them in the window frame.

Nice glass, but it should be the star here. Remove everything from the mantel and wall. Consider having a custom frame made for the glass that will set inside the recess of the windows. I don't know where you want to hang curtains, but these two little windows are not it. The stained glass says it all here. Simply get a group of glass candlesticks in a color from the panels for the mantel. If you have other windows to style with curtains, please post photos of them and the entire room.

The appearance of the blue in the stained glass will change depending on the light (or none at night) passing through. Fabric cannot stay matched to the changing appearance of the glass.

Hang your pieces like this with equal space around each side, (so it's centered).

Please let us see the windows you would like to put drapery on.

So I googled "shibori style curtains" Yes you can depending on which pattern you choose. Your stain glass has a few different blues so you should be fine.

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