@secilia I know you already got your answer from the wonderful @Amethyst, but if I might be so bold as to add, I wanted to share an in-depth post on Selenite/Satin Spar that you might find interesting.
Here are a few links specifically about the Desert Rose. Link 1 and Link 2 and Link 3
To break it down:
- Gypsum is the overall mineral species.
- Selenite is the crystalline variety of gypsum.
- Desert Rose is the name for these crystals when they grow in arid, sandy conditions, trapping sand grains to form “petals”.
Enjoy your lovely new crystal addtion! 
