In 1812, the mineralogist Friedrich Mohs , born in 1773, had created a reference scale of ten common minerals, ranked according to the increasing hardness. The scale starts with talc at 1 being the softest mineral and ending with diamond at 10 being the hardest mineral. Simply put: the higher the number, the harder the mineral. This way of definining the hardness of mineral had been used around the world. This scale is called the Mohs Scale of Hardness.