Summer Hills - A balance of Lemongrass, Rosemary and Benzoin essential oils helps to increase focus and re-vitalize the mind. This refreshing scent is best for daytime home and workspace usage during spring and summer. This scent can work as mosquito repellent as well. Lapis Lazuli is known for stimulating the desire for knowledge, truth and understanding. It also aids the process of learning and is excellent for enhancing memory.