I bought this as a TC labeled “Pink Polly Amazonica” but it appears more like a pink mint polly in my opinion. The leaves were fused together in vitro in the bag. I don’t think this will duplicate in other leaves. Fasciation is typically a mutation or deformity that occurs in the meristem of a plant. Meristems are where cells begin to form - similar to stem cells in humans, these cells divide and then specialize, becoming the cells that make up the leaves, stems and flowers. Sometimes a mistake happens, resulting in an abnormal growth. These mistakes can be caused by anything from a defect in the DNA code in the plant, to a viral infection, to insect damage. It can even be something environmental that causes this.