While certainly of Henan-type, stylistically this head compares well with other heads of similar date now in public and private collections that are identified as being originally from the Longmen Caves site. The hard, dark grey limestone, the carving of the facial features, especially the small pursed mouth, obliquely cut eyes and curved brows, the shape of the face with its full cheeks and small rounded double chin are features seen in all of these heads.
As the Manheim head is carved almost completely in the round, with only a small unfinished area to the nape of the neck, it is most likely not removed from a figure integral to the rock wall, but rather from the one of the separate Buddhas seated on isolated plinths within the cave-temple space. These figures, usually found alone or in triad groups, are more finely finished and carved from finer-grained distinct blocks of limestone, which would correspond with the exquisite quality and sensuousness of the present head. Compare a larger head in a Japanese collection, exhibited at the Osaka Municipal Museum of Art, Chinese Buddhist Stone Sculpture. Veneration of the Sublime, 1995, cat. no. 57, and illustrated by Sun Di, ed., Comprehensive Illustrated Catalogue of Chinese Buddhist Sculptures in Overseas Collections, vol. 5, Beijing, 2005, p. 1003, with almost identical proportions of the narrow head, high usnisa, deeply carved eyes and bud mouth.
Complete seated figures of Buddha in the round were developed during the peak phase of sculptural development at the Longmen grottoes under the sponsorship of Empress Wu Zetian in the second-half of the eighth century, such as the famous Fengxian Temple and the group of impressive Leigutai Caves, whose figures are executed with the same exquisite precision and plump femininity as the Manheim head. See Zhongguo Meishu Quanji, Diaosu - 11 - Longmen Shiku Diaoke, Beijing, 1988, figs. 193, 195, and 196. In 1925, Osvald Sirén illustrates three such isolated figures within the Xiang Shan cave-temple complex on the opposite side of the river from the main caves at Longmen. See O. Sirén, Chinese Sculpture from the Fifth to the Fourteenth Century, vol. II, (1998 reprint), pl. 462.
A very similar head can be seen on a seated figure of Buddha dated to the Tang dynasty excavated from the Fengxiansi Temple site, and now in the Longmen Caves Research Institute, illustrated in Ryumon sekkutsu (Longmen Caves), Miho Museum, Kyoto, 2001, pp. 84-5, no. 43.