6176492 Turban Helmet, c.1478??0 (steel, iron, silver) by Turkish School (15th century); height: 28.3 cm; Metropolitan Museum of Art, New York, USA; (add.info.: Turkish or Iranian helmet inscribed with the name of the sultan T Yaqub bin Uzun Hasan of the Aq Quyunlu (White Sheep Turkoman), ruled 1478-90 11th sultan of Sunni Oghuz Turkic tribal federation that ruled parts of present Eastern Turkey, Armenia, Azerbaijan, northern Iraq and Iran 1378-1501.).