This is a tie-releaser for your third eye, quickly cutting mental cords holding you back allowing you to regain control in the present. Agate returns any coercing energy to its source, freeing you to live life as you wish.
Hexagonal shaped crystals are used for protection and cleansing. It symbolizes strength, protection, and helps balance opposing forces. 
It can Also be used as a pendulum. Which assists with finding answers in a ritual called pendulum dowsing. 
 
Fun fact, wearing Agate especially around one's neck helps keep evil and negativity away.