Brown colour of contusion is due to
age of contusion Time since injury Color change First day red(hemoglobin) 2-3 days blue (deoxyHb) 4-5 days bluish black/brown(hemosiderin) 5-6 days greenish(hematoidin) 7-10days yellow(bilirubin) By 14 days normal ref: FORENSIC MEDICINE AND TOXICOLOGY Dr PC IGNATIUS THIRD EDITION PAGE 118
Hematoidin
Reduced haemoglobin
Hemosiderin
Bilrubin
Mechanical injuries