Relating to or composed of chalk; resembling or containing cretaceous materials in geological or chemical terms.
From Latin cretaceus (chalk-like) with the systematic suffix -ic. This is a more technical variant of cretaceous used in chemistry and mineralogy.
Geologists use both cretaceous and cretacic, but cretacic is the more technical term—showing how scientific fields sometimes develop parallel vocabulary to be more precise about exactly what they're describing.
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