Silicon

Silicon
Promotes a positive energy for all situations
Can enhance communication
Brings a feeling of lightness and a sense of security
Gently balances masculine and feminine energy 
Can sharpen mental activity and focus
Promotes discernment
Can be helpful for enhancing manual dexterity 
Purifies the body and mind
Silicon AKA Silicon Carbide is a material used for grinding and polishing
 
These are priced by weight and not necessarily by size.e