Aluminium is a good electrical conductor and is often used in electrical transmission lines. It is cheaper than copper and weight for weight is almost twice as good a conductor. When evaporated in a vacuum, aluminium forms a highly reflective coating for both light and heat.
Nelson Mandela had a large family and had 13 brothers and sisters.  Of all of his siblings, he had one full brother and one half  brother.
Mr Mandela was born into the royal family of the Tembu at Qunu, near Umtata, on 18 July 1918. The capital of the former Transkei, and now of the Eastern Cape Province. His father was the principal councillor, to the Acting Paramount Chief of Thembuland.