Cascarilla repels negative energy and the vibration of negative energy.
Different uses:
1.  Purification baths.  See the description of one such bath here: Bath for Purification
2.  As a piece of chalk to draw sigils, and circles of protection for Magickal rituals.
3.  This is great to have if you are going to meditate, astral project or perform visualizations.  You can use it as a powder and “dust” yourself with it or you can use it as a chalk and make the sign of the cross on different areas of your body (back of neck, forehead, temples, hands, chest and bottom of feet).
4.  If you have psychic abilities (Mediumship, Empathic, Clairsentient, Clairvoyant, etc), you can dust yourself or make the sign of the cross as previously mentioned, and it protects you from psychic attack and “energy vampires.”
5.  Cascarilla also keeps non-corporeal beings (spirits, ghosts, demons, etc) away from you!
*  If you feel like your home may be haunted, this would be a very good repellent (after a thorough house cleansing!!).  Be warned–if you have spirits around that you like talking to, you may find it more difficult to communicate with them!  Cascarilla does not discriminate between good and evil–it just provides a barrier between the physical and non-physical world.
6.  House protection (inside the home): use as a piece of chalk.
*  Going around the house clockwise, etch the sign of the cross on either side of the door, above the door and on the threshold.  When doing the windows–do above, below, and both sides of the window.  Do this with all doors and all windows of the home.
7.  House protection (outside perimeter of home).