The short version
When researchers looked closely at the mineral grains scattered through high-carbon shungite from the Maksovo deposit, they found more than quartz and silicates. Sitting inside the black carbon rock are micrometre grains of
native gold, native tungsten, molybdenite, nickel minerals, and an enrichment of rare-earth elements.
What's actually in there
From the Karelian Research Centre study (Sadovnichiy and Rozhkova, 2014):
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Native metals: native iron, lead, tungsten, and
gold - the gold as grains a few micrometres across in the massive (dense) rock varieties
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Molybdenite (the molybdenum sulfide): grains up to 200 micrometres
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Nickel minerals: millerite and gersdorffite
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Rare-earth elements: concentrated mainly in the massive shungite, confirmed by ICP-MS
Why it's worth knowing
Shungite is usually described as "carbon plus a silicate mineral matrix." That's true but undersells it: the rock is a genuine
ore-grade mineral cabinet. Two billion years of geology trapped not just fossil carbon but native precious and rare metals alongside it. The gold isn't enough to mine your stones for - the grains are microscopic - but it tells you something about the extraordinary chemistry of the Onega basin when this rock formed.
It also helps explain the trace-element fingerprint other studies report (the uranium, thorium, vanadium, titanium): this is a deposit that concentrated a remarkable range of elements in one place.
Sources
- Sadovnichiy R.V., Rozhkova N.N. (2014), "Минеральные ассоциации высокоуглеродистых шунгитовых пород Максовской залежи (Онежская структура)", Труды Карельского научного центра РАН:
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