The best replacement for chert is flint.

The best alternatives to chert are rated as following:
★★★★★  flint
★★  jasper

Your alternative for chert is not listed? Suggest!
Speaking about chert, one probably shouldn't forget about limestone.

Other search terms related to chert and their ratings are:
★★★★★ limestone
You have in mind a companion for chert and it is not yet here? Propose!



Google Trends

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chert
flint
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