I can assure you that they are definitely bougainvillea flowers that I folded. In fact there appears to be quite a few varieties and they do possess different colours: https://en.wikipedia.org/wiki/Bougainvillea
You are right in that they are difficult to fold, but not because of the size of petals (I fold models no bigger than from a 1cm x 1cm square cut from the petal), but because of the curvature of the petals that makes it difficult to press and work with.
You are right in that they are difficult to fold, but not because of the size of petals (I fold models no bigger than from a 1cm x 1cm square cut from the petal), but because of the curvature of the petals that makes it difficult to press and work with.