Natrolite is a sodium aluminum silicate crystal.  It is said to be one of the most powerful zeolites: stones that help create powerful personal changes.  It's usually colorless, but can also be yellow, grey or white.  It often forms long, slender crystals, sometimes in clusters, which gives it the nickname of needle stone.  
    Natrolite is said to be one of the best stones for stimulating the third eye (forehead) and crown chakras: the energy centers most significant for spiritual growth.  It also provides psychic protection, preventing dark forces from attacking you while you are in a vulnerable state such as meditation.  It can help dissolve energy blockages anywhere in the body and it also stimulates the nervous system.  It also is an aid in communicating with Light Beings that dwell in higher dimensions.  It helps awaken dormant senses and abilities.  In short, Natrolite is very good as a tool for spiritual growth.
    On the physical and mental level, Natrolite is said to help those with fear of water and those with water related illnesses such as water retention and edema.  It is very good at stimulating the brain.