Spheroidal Propellant Particle
Definition
A smooth, approximately spherical particle of ball-type smokeless powder 50-300 micrometres in diameter, identifiable under SEM by its distinctive morphology. Presence in blast debris indicates smokeless powder was a component of the device.
- Field
- Forensic explosives analysis
- Powder type
- Ball-type smokeless powder
- Size range
- 50 to 300 micrometres
- Detection method
- SEM (scanning electron microscopy)
- Significance
- Indicates smokeless powder as a device component
Common questions
Why is particle shape enough to identify ball powder without chemical testing?+
The smooth, near-spherical morphology from the ball manufacturing process is visually distinctive under SEM, but examiners typically confirm the identification with elemental analysis such as EDX rather than relying on shape alone.
Can spheroidal particles survive a device detonation intact?+
Unburned or partially burned particles can survive and be recovered from blast debris, which is why their presence is used as physical evidence that smokeless powder was part of the device even after an explosion.
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