GSR Pb-Sb-Ba Signature
Definition
The classical elemental signature of inorganic gunshot residue: lead from the bullet core, antimony from the priming compound, barium from the priming oxidiser. Read by EDXRF on a hand swab as a triage screen and confirmed by SEM-EDS particle morphology at CFSL Pune.
- Elements
- Lead, antimony, barium
- Lead source
- Bullet core
- Antimony source
- Priming compound
- Barium source
- Priming oxidiser
- Workflow
- EDXRF triage swab, SEM-EDS morphology confirmation
Common questions
Why is EDXRF used first instead of going straight to SEM-EDS?+
EDXRF is fast and non-destructive, letting a laboratory screen a hand swab for the presence of the lead-antimony-barium signature within minutes to decide whether the sample warrants further work. SEM-EDS is slower and more resource-intensive but adds particle-shape evidence that EDXRF cannot provide.
Why does SEM-EDS confirmation matter if EDXRF already found the right elements?+
Lead, antimony, and barium individually occur in many everyday sources, from brake linings to fireworks to some occupational dusts, so elemental presence alone is not conclusive. SEM-EDS examines whether the particles also have the characteristic spherical, fused morphology of gunshot residue, which is much harder to mimic environmentally.
Related terms
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