A fragrance free and preservative free oil that's pressed
from a desert shrub, jojoba is actually a vegetable wax
and will get solid at cold temperatures.  It's the oil most
similar to natural skin oils.  That quality makes jojoba
particularly beneficial in facial and hair formulations.
Adding jojoba oil to your carrier oil base and formulations
will extend their shelf life.  Jojoba stays fresh indefinitely
so it's an excellent base for perfume blends.