Natural long dark brown hair from South America

The hair has been cared with very good quality products for 5 years. It is hair that has never been dyed and to check its quality, if you wish, the person can do the following test and that is to take a strand of hair and set it on fire with a briquGet. Like dyed hair, when it is burned it smells like chemicals and this does not happen to natural hair, this is a way they can verify that it is natural hair.