Thaddäus (taddeo) Mayer ( 1814 - 1856 ) was a Czech painter. Thaddäus (taddeo) Mayer s works have been put up for auction numerous times, with realized prices surpassing estimated prices, varying from 378.43 USD for A PORTRAIT OF GENTLEMAN, SEATED THREE-QUARTER LENGTH, WEARING A BLUE COAT AND WHITE CHEMISE in 2006 to 3421.27 USD for Fr. Thadd√§us Mayer (1814 Katherov (Bohemia) - 1856 Prague) in