Stratigraphic and Microstructural Diagnosis of Imperial Coral-Red Ground Porcelain of the Qianlong Period: Application of the Beinos Method

Abstract

This article applies the stratigraphic “Beinos method” of micro-diagnosis to an imperial double-gourd vase with a coral-red ground and famille-rose decoration, attributed to the Qianlong period (1736–1795). The study includes macro- and microscopic observations, reconstruction of the stratigraphic sequence of enamel and glaze application, and comparative analysis with published museum examples. Special attention is paid to the role of manganese outlines, the technology of the red ground, the characteristics of green and yellow-green enamels, and the use of reserved white porcelain body as a painting base.

Object Description

• Catalogue number: QL-GR-GRNT-22-FR-01, QL-GR-GRNT-22-FR-02

• Type: porcelain double-gourd vase with famille-rose decoration (pomegranates and peonies

• Period: Emperor Qianlong (1736–1795), Qing dynasty

• Provenance: Imperial kilns, Jingdezhen

The vase is covered with a coral-red ground enamel of exceptional depth and evenness. Decoration in famille-rose technique includes pomegranates with open seeds, peonies, chrysanthemums, and leaves, complemented with gilding. The base is coated with turquoise glaze, bearing a six-character underglaze-blue Qianlong seal mark.

Methodological Basis: the Beinos Method

The Beinos method is a stratigraphic micro-diagnosis that reconstructs the decorating sequence by observing enamel and glaze layering. It reveals characteristic techniques of the imperial workshops.

Applied to this vase, the method revealed a multi-stage process:

1. Forming and biscuit firing.

2. Application of underglaze-blue mark on the base.

3. Transparent glaze over the body; high-temperature firing (~1300 °C).

4. Turquoise glaze applied to the base and interior.

5. First contouring stage (manganese/iron); some lines lie beneath the ground.

6. Coral-red enamel ground (珊瑚紅 shānhú hóng), low-temperature firing (~800–850 °C).

7. Famille-rose decoration (pink, green, yellow enamels) within reserves.

8. Second contouring stage for line reinforcement.

9. Final gilding.

Thus, contour lines were applied in at least two stages—before and after the red ground.

Microstructural Observations

Outlines

• Executed with manganese-based enamels, often mixed with iron/copper.

• Two types of lines: early, partly covered by red enamel, and later, crisp lines painted over colored enamels.

• Microbubbles along line edges indicate low-temperature firing of manganese compositions.

Red Ground

• Smooth surface with oily sheen.

• Microbubbles and glassy inclusions indicate copper and iron in a lead-borosilicate matrix.

• Fine craquelure at the foot is a diagnostic 18th-century feature.

Green and Yellow-Green Enamels

• Famille-rose enamels show a vitreous structure without craquelure or iridescent weathering.

• This sharply contrasts with Kangxi greens (famille-verte), which show phase separation, craquelure, and iridescence.

• Modern studies (Hou et al. 2021; Zhao et al. 2023) confirm that Qianlong enamels were stabilized with Pb-arsenate opacifiers, producing smoothness and gloss.

White Reserves

• White petal areas are not painted enamel but reserved porcelain body.

• Painting directly on white porcelain is a hallmark of high-status mid-18th century wares.

Gold

• Applied last, over enamels and outlines.

• Shows natural wear consistent with 18th-century gilding.

Comparative Analysis

• Private collection (Dronova, 2016): a coral-ground vase with birds and peonies (What You Need to Know About Antique Chinese Porcelain, Moscow, 2016, p. 276. DOI: 10.5281/zenodo.16794377) demonstrates identical contouring and stratigraphy.

• Palace Museum, Beijing: a vase with a more “brick-red” ground shows recipe variation in copper-red enamels of the Qianlong period.

• Victoria and Albert Museum, London: coral-red famille-rose vases confirm broader stylistic and technological trends.

Diagnostic Significance

The Beinos method highlights key diagnostic markers:

• Two-stage outline application (early under red, late over enamels).

• Coral-red ground with microbubble structure.

• Green famille-rose enamels without iridescence or craquelure (unlike Kangxi).

• Use of reserved white porcelain body for decoration.

• Stratigraphy: outline → red ground → colored enamels → reinforced outlines → gilding.

All features confirm the imperial origin of this vase from the Jingdezhen kilns under Qianlong (1736–1795).

Conclusion

The stratigraphic Beinos method demonstrates that imperial coral-red porcelain of the Qianlong period was produced in multiple stages, including repeated contouring, red enamel ground, famille-rose painting, and gilding. Two-phase manganese outlines, improved green enamels, and the use of reserved white body are key diagnostic signs of 18th-century court wares.

Keywords

Qianlong, Qing dynasty, imperial porcelain, Beinos method, stratigraphic diagnosis, coral-red glaze, manganese outlines, famille-rose enamels

References

• Hou, X. et al. Microstructural and compositional analysis of Qing dynasty famille-rose enamels. Journal of the European Ceramic Society, 2021.

• Zhao, L. et al. Scientific study of enamelled porcelain of the Qing imperial kilns. Ceramics International, 2023.

• Dronova, N. D. What You Need to Know About Antique Chinese Porcelain. Moscow: OOO “Tipografiya KEM”, 2016, p. 276. DOI: 10.5281/zenodo.16794377. ISBN 978-5-9908782-6-6.

• Palace Museum (故宫博物院). Complete Collection of Treasures of the Palace Museum: Famille Rose and Enamelled Porcelain. Hong Kong: The Commercial Press, 2008.

• British Museum Collections Database. Famille-verte and famille-rose enamels: technical notes. London, accessed 2024.

• Beurdeley, M., Raindre, G. Qing Porcelain: Famille Verte, Famille Rose. Geneva: 1987.

• Kerr, R., Wood, N. Science and Civilisation in China, Vol. 5: Chemistry and Chemical Technology, Part 12: Ceramic Technology. Cambridge University Press, 2004.