Rock Quartz, commonly known as Clear Quartz has many, many healing benefits. Below are just a sample to get you started.
Aids in keeping body, mind and spirit in balance
Helps aid with memory and capacity to concentrate
Works with the Crown Chakra
Rock Quartz aids with the overall health of your body, mind and spiritual wellbeing.
This is a busy crystal with many advantages to be had and thusly my favourite crystal to have on me. Look into it yourself, if your not familiar with it already you won't be disappointed!