Medium : 2.50-3.50 cm
Large : 3.50-4.50 cm
The Shungit or Shungite is a black and light stone composed essentially of organic carbon (between anthracite and graphite) . This mineral has a unique chemical composition on the planet, it is a combination of aluminum, carbon, silicon, iron, magnesium, phosphorus, calcium, sulfur and more macroelements from the crust.
It is considered one of the oldest minerals on Earth and is the only one that contains fullerenes or fullerenes, widely used in new studies of nanotechnology and medicine.
The piece you receive may differ slightly from the photo shown as the minerals are natural and no piece is identical. The size is approximate.