Shiny Things - February 6th, 2008

07:53 am - Indigo, Sand Dollars, Comedogenic

1.  Why is there a seventh color-indigo-in the rainbow, that isn't discussed in optics? What does indigo look like, anyway?

2. Where do sand dollars come from?

3. We have some skin lotion that says it is "non-comedogenic". Does that mean that it won't start something funny?