“chains of such weight as only notorious criminals were condemned to carry, were placed upon His [Bahá’u’lláh’s] neck”

One of the chains placed around Bahá’u’lláh’s neck in the Síyáh-Chál 

The Qará-Guhar fetters (lit. big and heavy), heavier than the intermediate weight of the Salásil chains (lit. iron chains) weighed about fifty-one kilograms or one hundred and ten pounds; a special wooden fork was supplied to the prisoner to help carry its weight. (David Ruhe, ‘Robe of Light: The Persian Years of the Supreme Prophet Bahá’u’lláh 1817-1853)