One piece of rough Silicon. Images to show variety
 
Silicon (Latin: silicium) is the most common metalloid. In Earth's crust silicon is the second most abundant element after oxygen. In its crystalline form pure silicon has a gray colour and a metallic lustre. It is similar to glass in that it is rather strong very brittle and prone to chipping.
 
Spiritually Silicon is said to help balance masculine and feminine energy, brings a feeling of light and peaceful serenity. It can also clear and open the Heart Chakra