Crazing
Definition
A mosaic network of intersecting surface fissures on burned bone, produced by differential contraction of the outer bone surface relative to the interior as temperature rises; polygon size and spacing reflect the rate of heating.
- Appearance
- Mosaic network of intersecting surface fissures
- Material affected
- Burned bone
- Cause
- Differential contraction of outer surface vs interior
- Diagnostic value
- Polygon size and spacing reflect heating rate
Common questions
How does crazing pattern help estimate heating rate?+
Rapid heating produces smaller, more tightly spaced polygons because the outer bone contracts faster than heat can dissipate inward, while slower heating allows larger, more widely spaced fissure networks to form.
At what stage of thermal trauma does crazing typically appear?+
It develops as bone dehydrates and organic content begins breaking down, generally before the bone reaches full calcination, making it a useful marker for reconstructing the heat exposure sequence.
Related terms
- Calcined Bone
- Bone heated to above approximately 700°C, resulting in complete combustion of the organic component (collagen), leaving only mineral hydroxyapatite; characterised by white...
- Delamination
- The separation of the outer table of bone from the underlying diploe or cortex in curved sheets during green-bone burning; produced by...
- Dry Bone Fracture Pattern
- Straight, longitudinal fractures running parallel to the long axis of a bone, following the Haversian structural directions; characteristic of bone burned after...
- Green Bone Fracture Pattern
- Curved transverse fractures running approximately perpendicular to the long axis of a bone, with a stepped or warped cross-sectional profile; characteristic of...
- Hydroxyapatite (HA)
- The calcium phosphate mineral [Ca10(PO4)6(OH)2] that comprises approximately 70 per cent of bone mass; survives fire at all temperature stages, sintering and...
- NFPA 921
- US National Fire Protection Association Guide for Fire and Explosion Investigations. The internationally accepted methodology Indian fire investigators and SFSL fire divisions...
- Pope-Smith Framework
- The 2004 analytical framework distinguishing perimortem from postmortem fire exposure using fracture geometry, cross-section colour uniformity, periosteal behaviour, and anatomical integrity; explicitly...
- Shipman Colour Stages
- The five-stage colour classification (yellow-tan, brown, black, blue-grey, white) published by Patricia Shipman and colleagues in 1984, corresponding approximately to temperature ranges...
- ZooMS (Zooarchaeology by Mass Spectrometry)
- A peptide mass fingerprinting method using collagen fragment masses to identify bone to species level; applicable to burned bone samples where conventional...