Brown color of contusion is true is due to -
the synopsis for forensic medicine & toxicology . Dr .ks.narayan reddy ,28th edition . Pg no . 108 Colour of the bruise indicates the age of bruise ,the colour change is due to the breaking down of haemoglobin into haemosiderin ,haematoidin and bilirubin by the action of enzymes . At first : red Few hours to 3 days : blue 4th day : bluish black to brown (hemosiderin ) 5-6th day : greenish (haematoidin ) 7-12th day : yellow (bilirubin ) 2 weeks : normal
Haematodin
Reduced hemoglobin
Haemosiderin
Bilirubin
Mechanical injuries