Prom dress or special occasion, iridescent, 10-12

This is such an interesting dress. It is an iridescent color. In some light it looks green, pink, Gray, the top part is spaghetti strapped w/ some sequins. The back has ties to give you a little bit more room in the chest. It also has a zipper back. Smoke-free home, nwt. It's floor-length. It says size 12 but I believe it runs small. Please let me know if I can provide measurements. It looks and feels like silk but it's 46% polyester & 54% nylon. It's lined. Measurements, across the hips 19 1/2.