Lapis lazuli is for Deep self knowledge.

Lapis has a hardness of 5 to 5.5 on mohs scale of hardness. It contains lazurite, calcite and pyrite.
Lapis is a metamorphic rock . humans have used this crystal from ancient times. This is used for third eye and throat chakra .It helps to enhance mental power by activating pituitary gland . It promotes clear understanding and intuition power and is effective against depression , promotes bounding and strengths idealism. It gives relief from migraine and headache . It over comes hearing loss , purifies blood ,boosts immune system . It alleviates insomnia , vertigo and lowers blood pressure