Shungites (Sh) are the black Precambrian rocks of Karelia (Russia) where the first natural occurrence of fullerenes was found. The presence of C_60 and C_70 in Sh-1 (concentration of carbon up to 92-98 wt.) 1 and in Sh-3 25-40 wt. carbon) 2 has been demonstrated. The discrepancy between Sh-1 and Sh-3 consists in their abundance. Sh-3 is among the most abundant carbon-rich rocks, and occupies thousands of square kilometers in Karelia, whereas Sh-1 is a more limited rock and is unique. Shungite carbon (C_Sh) is characterised by a fraction of closed shells consisting of graphite-like layers and of carbon black as aggregates of various carbons clusters 3. The presence of hollow closed shells led to the proposal of a fullerene-like model of C_Sh 4,5, where the globule is the unit of the structure. According to such a model, globules of C_Sh can be seen as aggregates of giant multilayer fullerenes 6. It this model is correct, the problem of fullerene detection will no longer exist. At the same time, fullerene extraction from Sh will be elementary and may be reduced in order to enrich Sh with C_Sh. However, the problem of fullerene extraction from Sh exists and is intimately bound to the difficulties of fullerene separation and its detection.
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