paramorph

mineral

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Last updated

July 1, 2026

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A paramorph is a type of pseudomorph, which is a mineral that has changed its internal structure or chemical composition but retains its original external shape. Specifically, a paramorph is a pseudomorph that undergoes a change in crystal structure without altering its chemical composition.12

An example of this transformation is when aragonite changes into calcite. While the external form may appear the same, the internal crystalline structure and physical properties are different. This process is distinct from other pseudomorph formations, such as substitution, where one mineral is replaced by another, or alteration, which involves changes in chemical composition.12

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pseudomorph
…composition (these pseudomorphs are called paramorphs; e.g., aragonite becomes calcite, and brookite becomes rutile); by the loss of an ingredient from the original compound (e.g., cuprite loses oxygen to form copper); by the addition of an ingredient to the original compound (e.g., anhydrite adds water to form gypsum, and cuprite…
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…composition (these pseudomorphs are called paramorphs; e.g., aragonite becomes calcite, and brookite becomes rutile); by the loss of an ingredient from the original compound (e.g., cuprite loses oxygen to form copper); by the addition of an ingredient to the original compound (e.g., anhydrite adds water to form gypsum, and cuprite…
Read More