When used for its metaphysical properties hematite is associated with the blood. Throughout history it has been used to heal blood disorders and to stop bleeding. It's also associated with power, strength and protection.
The root 'hema' or more correctly 'haema' is used in many medical terms relating to the blood. Haemoglobin is the protein in red blood cells that contains iron. Haematology is the study of the blood and associated diseases. Haemophilia is a rare condition in which the blood it not able to clot.