Converted into flint or flint-like material through geological or chemical processes.
From 'flint' plus '-ify' (meaning to make or convert into, from Latin 'facere', to make) plus '-ed'. The suffix '-ify' is productive in English for creating verbs meaning transformation.
Geologically, flintification happens when silica-rich solutions permeate organic material—wood can literally turn into flint over millions of years. It's one of nature's methods of preservation and transformation.
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