Looking for a children’s book about a butterfly

I had a story book as a child and I can’t remember the title or author. It was about a butterfly and it had gold foil details on the wings (similar to rainbow fish but gold) I can vividly remember the cover of it, it had a deep blue border with a golden frame and the main butterfly was in the foreground with blue/purple wings and golden details, behind that was a swarm of other butterflies (none of them had any gold details)

I know this is not a lot to go on but I really want to find this book.