CHINE, DYNASTIE QING, MARQUE INCISEE A QUATRE CARACTERES ET EPOQUE QIANLONG (1736-1795)

Compare with a extremely similar cloisonne enamel incense holder from the Qianlong period, illustrated by Zheng Xinmiao, (ed.), Compendium of Collections in the Palace Museum: Enamels 3 - Cloisonné in the Qing Dynasty (1644-1911), Beijing, 2011, pl.1.
See an almost identical example sold in Christie's London, 12 September 2018, lot 69.