Silsilat al-Ahadith al-Sahihah

It is narrated from Sayyiduna Abu Musa Ash'ari (may Allah be pleased with him) that the Messenger of Allah (peace and blessings of Allah be upon him) said: "Indeed, Allah the Exalted took a handful from all of the earth and created Adam (peace be upon him) from it. That is why the children of Adam were created according to the nature of the earth's soil: some are red, some are white, some are black, and some are in between these colors; some are soft, some are hard, some are impure, and some are pure."