Retrieving "Geologic Era" from the archives

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1. Crystallization Ages

   Linked via "eras"

   Temporal Classification Schemes
   Crystallization ages are broadly categorized based on established eons and eras, although recent findings suggest these divisions may be too coarse for resolving polymagmatic events. The following table outlines the generally accepted, though occasionally revised, classifications based on common mineral systems:
   | Age Classification | Approximate Time Range (Ga) | Defining Mineral System | Associated Tectonic Regime |