and which period has this artefact been dated to?
thirteenth-fourteenth century AD.
Bronze Head from Ife
It was probably made in the thirteenth-fourteenth century AD, before any European contact had taken place with the local population. 
this close relative of zn is used with nickel UNANSWERABLE how does this metal look like? Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. where can it be found abundantly? Large deposits are in Australia, Canada and the United States, with the largest reserves in Iran. how was it used in the early days of human civilization? Zinc ores were used to make the zinc–copper alloy brass, Judean brass from the 14th to 10th centuries BC contains 23% zinc. is it found in food sources as well? Yes, animal products such as meat, fish, shellfish, fowl, eggs, and dairy contain zinc. can you speak about some popular uses of the alloyed metal you mentioned before? Zinc oxide is widely used as a white pigment in paints and as a catalyst in the manufacture of rubber to disperse heat. has objects made from this been found in the african continent? Yes, the large portrait heads such as the Bronze Head from Ife of "heavily leaded zinc-brass".
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Bronze Head from Ife [SEP] Introduction
The Bronze Head from Ife, or Ife Head, is one of eighteen copper alloy sculptures that were unearthed in 1938 at Ife in Nigeria, the religious and former royal centre of the Yoruba people. It is believed to represent a king. It was probably made in the thirteenth-fourteenth century AD, before any European contact had taken place with the local population. The realism and sophisticated craftsmanship of the objects challenged Western conceptions of African art at the time. A year after its finding, the Ife Head was taken to the British Museum.