Opium weight, Hintha 1B, 2 ½ viss / 250 tical (3.715 g), Burma (Myanmar), ca. 1640

References: Hartmut Mollat "A Model Chronology of the Animal Weights of Burma (Myanmar)" Anthropos 104 / 2009, 533-542, 2009
Sylvia Fraser-Lu, Burmese "Opium" Weights, Arts of Asia, Volume 12 No. 1, January - February 1982, p. 74
Rolf and Ilse Braun, Opiumgewichte, Pfälzische Verlagsanstalt Landau, 1983 p. 123, fig. 11 and 37
Donald and Joan Gear, An ancient bird-shaped weight system from Lan Na and Burma, Silkworm Books 2002, Plate 1 (Opium Museum, Chiang Rai)
Permanent exhibition of the Bangkok Insurance Museum, 25 Sathon Tai Road, Bangkok, Thailand