Existence of a complexity threshold for mineral biosignatures and technosignatures

Determine whether a quantitative threshold in mineral complexity exists such that exceeding the threshold would classify a mineral as a biosignature or technosignature.

Background

Inspired by prior work using molecular assembly as a biosignature, the authors compute assembly indices for mineral unit cells and observe a continuum of values without an apparent threshold. They note that copy number and defects complicate direct interpretation of unit-cell complexity.

The unresolved issue is whether a clear complexity threshold can be defined for minerals that reliably distinguishes those produced by evolutionary or technological processes (biosignatures or technosignatures) from naturally formed materials.