This is a fritillary of some kind, but they're really hard to tell apart: https://northwestbutterflies.blogspot.com/2016/09/lesser-but-not-least-fritillaries.html
Hard to be absolutely certain without seeing the underside, but I would bet on it being a Dark Green Fritillary.
Lovely picture!
@ColinTheBald started
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This is a fritillary of some kind, but they're really hard to tell apart: https://northwestbutterflies.blogspot.com/2016/09/lesser-but-not-least-fritillaries.html