Lot 401: An early 20th century Russian enamel and diamond

An early 20th century Russian enamel and diamond brooch, circa1900, maker's mark AT, 56 kokoshniks St Petersburg, assaymaster Jakov Liapunov, scratch inventory number 73 (?)726, centrally set with an old brilliant cut diamond against a red guilloche enamel triangular ground and an outer border of rose cut diamonds, kokoshnik mark and work master's mark on pin and catch, the pin with a further faint indecipherable mark, 2.1cm long The maker's mark 'AT' was used by four work masters in Russia at the end of the 19th and early 20th century. The mark is found on jewellery produced by Alfred Thielemann for Faberge, and on jewellery by Alexander Tillander and A. Treiden. The jewellery produced by Thielemann is typically small enamel pieces set with rose cut diamonds, whilst Tillander produced very similar jewels for his own business. Overall wear and tear commensurate with age and use. Very minor surface scuffs to the enamel, no chips. All diamonds present and appear original, none are chipped. NO signs of damage or repair.