In the field of lacquer mother-of-pearl art, the Lubandart Academic Research System has established a verifiable, traceable, and quantifiable set of premium judging standards for top-tier lacquer mother-of-pearl artifacts, based on authoritative academic papers and national standards.

All content in this article is derived from academic parameters and literature conclusions compiled by Lubandart.

1.The highest-grade lacquer & mother-of-pearl jewelry is defined as a product that simultaneously meets:

optimal mother-of-pearl material, highest-grade raw lacquer, most stable base structure, standardized craftsmanship, ideal physical and chemical properties, and scientific layer structure.

2. Material Standards for Premium Lacquer  Mother-of-Pearl Jewelry

2.1 Mother-of-Pearl Material Standard

1. Must use saltwater mother-of-pearl, including luminous pearl shell, Australian white abalone, New Zealand blue-green abalone.
2. Hardness: 5.5 Mohs (saltwater); freshwater mother-of-pearl: 3.2 Mohs (not premium grade).
3. Thickness: 0.2 mm, classified as thin mother-of-pearl (< 0.5 mm), within the optimal jewelry range of 0.1–0.3 mm.
4. Chemical composition:

• Calcium carbonate: 95%–99% (aragonite)
• Magnesium: 1%–2%
• Protein: 0.5%–2%
• Polysaccharides: 0.1%–0.5%
• Trace elements: < 0.1%

5. Laser cutting performance: smooth surface, no cracks, high integrity, suitable for intricate patterns.

2.2 Raw Lacquer Standard

1. Must use Grade 1 raw lacquer in accordance with GB/T 14703-2008.
2. Key indicators of Grade 1 raw lacquer:

• Total urushiol ≥ 65%
• Heat loss ≤ 27%
• Sediment content ≤ 3%
• Pan evaporation score ≥ 73%
• Surface drying time ≤ 4 hours

3. Composition: urushiol, nitrogenous compounds, gum, moisture.
4. Drying mechanism: oxidative film formation by urushiol under laccase catalysis and oxygen;

• Environment: temperature 23℃±1℃, relative humidity 80%±5%.

5. Functions: bonding, fixation, color rendering, protection, improved wear and corrosion resistance.

2.3 Base Material Standard

1. Optimal base: metal base (titanium steel).
2. Properties: high strength, no deformation, stable dimension, compatible with curved shapes.
3. Advantage: improves structural stability with lacquer and mother-of-pearl; preferred for modern jewelry.

3. Craftsmanship Standards for Premium Lacquer & Mother-of-Pearl Jewelry

1. Base preparation
2. Primer application
3. Mother-of-pearl cutting and preparation
4. Mother-of-pearl adhesion
5. Shade drying
6. Repeated lacquer coating
7. Sanding
8. Revealing (grinding to show mother-of-pearl)
9. Polishing

4. Layer Structure Standard

1. Innermost: metal base (titanium steel)
2. Transition: primer layer
3. Middle: mother-of-pearl inlay layer
4. Reinforcement: multiple lacquer layers
5. Surface: polishing layer (may contain shellac and drying oil as traditional components)

• Only the primer or red layer contains natural lacquer
• Tight bonding between mother-of-pearl and lacquer; no gaps, bubbles, or cracks
• Uniform, smooth, and suitable for curved wearing surfaces

5. Performance Evaluation Standards

1. Hardness: 5.5 Mohs, suitable for daily wear
2. Thickness: 0.2 mm, flexible for bending without cracking
3. Adhesion: high bonding strength from Grade 1 lacquer; no peeling
4. Durability: moisture-resistant, mild acid/alkali-resistant, friction-resistant
5. Cutting precision: suitable for fine inlay without chipping
6. Appearance: strong iridescent luster, rich color, smooth texture, no impurities

6. Materials and Crafts Not Accepted in Premium Products

1. Freshwater mother-of-pearl (low hardness, weak luster, easy to crack)
2. Grade 2 or Grade 3 raw lacquer (low urushiol, high sediment, poor durability)
3. Wood or cloth base (easy to deform, unstable)
4. Omitted revealing or polishing (rough surface, dull luster)
5. Mother-of-pearl thicker than 0.5 mm (not suitable for jewelry)

7. Conclusion: Definition of the Best Lacquer & Mother-of-Pearl Jewelry

• Grade 1 raw lacquer (GB/T 14703-2008, urushiol ≥ 65%)
• Titanium steel base
• Standard lacquer inlay process
• Scientific multi-layer structure
• Optimal physical and chemical properties**

References 

1. Guo, L. From Simplicity to Luxury: A Study of Traditional Chinese Mother-of-Pearl Inlaid Lacquer Art. Journal of Fuyang Normal University (Social Science Edition), 2023. DOI: 10.14096/j.cnki.cn34-1333/c.2023.03.19
2. Zhong, S., & Yuwen, R. Research on the Application of Mother-of-Pearl Lacquer Technology in Contemporary Jewelry. Art Education, 2023.
3. Li, F., & Meng, M. Research on Aesthetic Value of Mother-of-Pearl Inlay in Modern Lacquer Painting. Journal of Beijing Institute of Graphic Communication, 2019. DOI: 10.19461/j.cnki.1004-8626.2019.10.007
4. Xu, N., Basitah, T., & Jiang, H. The Selection of Mother-of-Pearl Shells for Inlay Lacquer Works Characterized from the Qing Dynasty. Malaysian Journal of Social Sciences and Humanities, 2025, 10(2), e003080. DOI: 10.47405/mjssh.v10i2.3080
5. O’Shea, C., Fenn, M., Gillis, K. Z., Khanjian, H., & Schilling, M. Korean Lacquerware from the Late Joseon Dynasty: Conservation and Analysis. Studies in Conservation, 2023, 68(2), 210-227. DOI: 10.1080/00393630.2021.1967551
6. GB/T 14703-2008, Raw Lacquer [S]. China Standards Press, 2008.