Price is for 1 piece weighing 14-18 grams. 
Agni Manitite is what is known commonly as a pseudo-tektite - similar in appearance, but is instead from terrestrial origins, in this case ancient volcanic activity. These are ancient forms of Obsidian, and are also known variously as Cintamani Stone or Pearl of Divine Fire. Agni Manitite can help you to create and manifest the change that you desire. Increases willpower and stimulates the creativity. 
It also helps to shield the mind from negative thoughts and begin the process of transformation. 
Chakra- Solar Plexus
Zodiac- Aries and Gemini