SEM investigation of minor constituents of carbide materials prepared from shungite rocks

The “SiC-Al₂OC”-based composite prepared from Karelian shungite rocks has been studied by X-ray diffraction analysis and scanning electron microscopy. SEM investigation has been done to determine the mode and distribution of admixture constituents. It is found that the most common minor phase represents Al–Fe–Si–C-based alloys. Special attention has been given to describing the noble metals admixtures. It is revealed that the noble metals phases occur as separate microsized grains, most of which have been indicated as Au–Ag–Hg amalgam and rarely as Pt-rich compounds. The obtained data can be mainly used to advance technologies for manufacturing carbide-based composite materials from natural carbonaceous rocks.