Here’s a very short video (only 17 seconds; and the picture is narrow) of a ladies’ waistcoat with a very shiny satin back:
http://www.youtube.com/watch?v=Gb-WcgvTI-Y
It’s probably the shiniest waistcoat back I’ve ever seen. Have you ever seen an even shinier waistcoat back? I’d like to hug the girl while she’s wearing her waistcoat. I’d like to stand behind her stroking her satin and watching it shimmer. I’d play with her back adjuster undoing it and then adjusting it as tight as possible so as to accentuate her waist.