Price is for 1 tumble, picked at random. 

Terahertz is a man-made gemstone that was invented by Japanese scientists in order to protect the body against electromagnetic smog and harmful radiation.
This stone is actually believed to be a very strong healing stone that possesses very high oscillating frequency as well as thermal conductivity.

Terahertz stone can energize inner body energy which is extremely useful if you need a boost. 
Terahertz helps in clearing the mind. It can help ease your mind from stress and worries and is also beneficial if you are using brain often, such as for studying or if you have an academic career or job which requires a lot of thinking.
Terahertz is one of the rarest stones in the market. And since it is quite difficult to obtain, it is more expensive compared to other stones that are widely available in the market.
I use this on my hip which has arthritis and can feel the healing effects, a powerful stone.