Reflections in my knop

I was trying to take a photo of the faceted drop that was throwing off rainbows. It wasn't working then I noticed an upside down reflection in the bit of glass above. Any round shaped bit of decorative glass is called a knop. You get them a lot on wine glass stems. Knopf is German for button. The dictionary definition for knop is - a small knob or similar rounded protuberance, especially for ornament. Makes you think.