Small dark green

I like the idea of a border of the yellowish fabric that you used in the body of the quilt, the same width as you had in the yellow blocks that 'sash' between each block. Then I'd cut wider piano keys of all the fabrics you used in the center to make longer lengths, attach to the sides and then cut a scalloped edging to soften all the angular edges in the center. Then it doesn't take away from the beautiful blocks. Wonderful quilt!

I would affix a narrow beige border (the same fabric framing each block), then another dark border the same width. I think you need to visually connect the beige "framing" then stop your eye with another narrow dark border BEFORE you audition a wider border of yet another fabric. Love the colors and layout!

How about NO border at all?
Just bind it with your "yellowish" fabric!
I've been seeing "no border" quilts a lot lately!
:)

beigh boarder then paino keys in all the colours

I really love this quilt. It is so soothing. But I don't think I would use black. If you can, use one of the fabrics in the quilt, then another border of the background fabric.

I'd do the narrow border in the sashing color, and then do the final border wider (maybe 4" or so?) in piano keys that are the same width as your fabric strips in the quilt. If you really want a nice finish I'd do a slight scallop on that final border to soften the quilt as there are so many lines (no curves) in the quilt. Your quilt is lovely!

Wow - just realized I commented on this quilt 2 1/2 months ago -- but am glad I'd do the same thing at least! I need a cup of tea...... : )

Its a beauty no matter which of the selections of border you choose