Various rock samples containing or consisting of shungite, a rare material named for the village of Shunga in northern Lake Onega. It is amorphous, not crystalline and consists of carbon which has not converted to graphite, despite being 2 billion years old. Pyramid sample is cut into shape for decorative purposes. Preview of PAS-dataset https://doi.org/10.23729/4e1ed93e-c112-4b2e-9939-8bf29c3f4010

2021