We spend a good chunk of our time fussing over our hair. Hair characteristics and related medical and social inferences sway our perceptions of each other. Humans have always regarded hair as a subject of vanity and stereotyping, but how much do we really know about it? If you think you know all there is to know about your hair, think again. Here are some facts that might surprise you.

Fact: Each strand of human hair contains 14 different elements, including traces of gold. Philippe Walter and his colleagues at the Pierre and Marie Curie University in Paris found gold nanoparticles in human hair.

Fact: Hair can be used to clean up oil spills. When the Cosco Busan oil spill occurred in the San Francisco Bay in 2007, some eco-friendly volunteers used mats of human hair to clean the beach as hair absorbs oil from water. It works as a natural sponge.

Fact: Your hair contains information about what has been in your bloodstream, including minerals and drugs. Hair is the most common type of forensic evidence.

Fact: Your hair is strong. A single strand of human hair can hold 100g in weight. So all the hair on a head together could support 12 tonnes, which amounts to the weight of two elephants.

Fact: The hair of Asian people is more likely to grow thick and long. The hair of African people is likely to be fine and furrowed. It is entangled to offer insulation against the harsh sun.

Fact: The only thing that can’t be identified by human hair is gender. The hair of men and women is identical in structure.

Fact: Black is the most common hair colour. The rarest hair colour is red, which exists in about 1 percent of the world’s population. Blonde hair can be found in 2 percent of the population.

Fact: Hair can grow anywhere on the human body, except on the palms of the hands, soles of the feet, eyelids, lips, and mucous membranes.