Let's look at the herb Calendula.  It is often referred to as"Pot Marigold", although the leaves and flowers are quite different from regular marigolds.  Calendula has been used medicinally for thousands of years.  In my reading, I have found many references for its use.  Combined with soothing oils and butters, it has been found to help  skin repair from chafing and abrasions.  I have read that it has been used for Gastrointestinal disturbances.  Calendula has also been used for coloring material a pale to bright yellow . 
Calendula has been called the "Poor Mans Saffron"--being used in rice dishes to create the yellow in yellow rice dishes.

I use Calendula in the making of all my soaps.  Many of which contain both the flower petals, and some containing only Calendula oil extract, ( made by macerating the petals with a mortar and pestle, pouring olive, jojoba, or sweet almond oil over the macerated petals, and letting the concoction sit in a cool dark place for several weeks. The petals are then strained away, leaving an oil with the benefits of the Herb).

Has anyone had any other experiences with Calendula?