I. Examination and comparison of antique craftsmanship:
Antiques was valuated visually and compared with database on the basis of ware form, decoration, pigment, glaze, clay and reign mark.
II. Favorable scientific appraisal :
Antiques was valuated by micrograph and compared with database on account of pigment, glaze, clay and glaze bubbles.
Antiques was valuated by micrograph and compared with database on account of pigment, glaze, clay and glaze bubbles.
III. 16 steps of antique appraisal:
A. Craftsmanship appraisal by visual appraisal and library database:
A. Craftsmanship appraisal by visual appraisal and library database:
(1)Ware form: Each era had distinct ware form in favor. Database of ware form helped defining era of production.
(2) Volume / Weight: Every period designed ware in different thickness. For instance, ware from Yuan dynasty performed heavy and thick style and ware from Ming and Qing dynasties tended to be lighter design.
(3) Decoration: decoration features were crucial to division of history into periods. The drawing and style varied to fit in with changes of dynasties. Specific decoration in specific period was filed in decoration database.
(4) Reign mark: There were several antiques with reign mark which was compared to prove genuineness.
(5) Glaze Color: When there is no ash, there is no glaze. Ash had direct influence on glaze color in grayish, bluish, or whitish tone in terms of ash amount, plant ash, or mineral ash. For example, underglaze-blue porcelains of Ming dynasty presented stable glaze color and those from Qing dynasty presented bright translucency.
(6) Glaze Quality: Glaze exquisiteness, glaze thickness, orange peel effect, or sand hole was one of features for distinguishing antique era.
(7) Trimming: Trimming of ware and its foot ring varied in distinct dynasty. Taking example from Yuan dynasty, large ware was jointed without much trimming. Meticulous trimming and no scraping mark were peculiar to Ming and Qing dynasty.
(8) Clay Color: Diverse formula of clay material existed in distinct kiln, region, and period. Thus, fired porcelains presented diversified clay color as like yellow, gray, and white.
(9) Clay Quality: Clay panning affected degree of exquisiteness. Citing an instance for clay in Yuan dynasty, it was less refined than that of Ming dynasty. By contrast, the clay of Ming dynasty had firmer texture and fewer air holes and impurities than that of Yuan dynasty.
(10) Iron Rust Spots: Iron rust spots were produced by pigment of underglaze-blue porcelains that contained cobalt oxide. The pigment in used of coloring agent was generally divided into local pigment and imported pigment. After firing the porcelains, imported pigment produced iron rust spots with silver reflection due to high amount of ferric oxide. On the other hand, local pigment didn’t produce iron rust spots. Appraising antique included to compare information and photos of iron rust spots on underglaze-blue porcelains in every period.
B. Favorable scientific appraisal by technical examination and data comparison:
(11) Magnification of pigment, glaze, clay, and glaze bubbles: Database had stored up magnification of porcelains from each period on pigment, glaze, and clay by magnifying power of 10X to 200X.
(2) Volume / Weight: Every period designed ware in different thickness. For instance, ware from Yuan dynasty performed heavy and thick style and ware from Ming and Qing dynasties tended to be lighter design.
(3) Decoration: decoration features were crucial to division of history into periods. The drawing and style varied to fit in with changes of dynasties. Specific decoration in specific period was filed in decoration database.
(4) Reign mark: There were several antiques with reign mark which was compared to prove genuineness.
(5) Glaze Color: When there is no ash, there is no glaze. Ash had direct influence on glaze color in grayish, bluish, or whitish tone in terms of ash amount, plant ash, or mineral ash. For example, underglaze-blue porcelains of Ming dynasty presented stable glaze color and those from Qing dynasty presented bright translucency.
(6) Glaze Quality: Glaze exquisiteness, glaze thickness, orange peel effect, or sand hole was one of features for distinguishing antique era.
(7) Trimming: Trimming of ware and its foot ring varied in distinct dynasty. Taking example from Yuan dynasty, large ware was jointed without much trimming. Meticulous trimming and no scraping mark were peculiar to Ming and Qing dynasty.
(8) Clay Color: Diverse formula of clay material existed in distinct kiln, region, and period. Thus, fired porcelains presented diversified clay color as like yellow, gray, and white.
(9) Clay Quality: Clay panning affected degree of exquisiteness. Citing an instance for clay in Yuan dynasty, it was less refined than that of Ming dynasty. By contrast, the clay of Ming dynasty had firmer texture and fewer air holes and impurities than that of Yuan dynasty.
(10) Iron Rust Spots: Iron rust spots were produced by pigment of underglaze-blue porcelains that contained cobalt oxide. The pigment in used of coloring agent was generally divided into local pigment and imported pigment. After firing the porcelains, imported pigment produced iron rust spots with silver reflection due to high amount of ferric oxide. On the other hand, local pigment didn’t produce iron rust spots. Appraising antique included to compare information and photos of iron rust spots on underglaze-blue porcelains in every period.
B. Favorable scientific appraisal by technical examination and data comparison:
(11) Magnification of pigment, glaze, clay, and glaze bubbles: Database had stored up magnification of porcelains from each period on pigment, glaze, and clay by magnifying power of 10X to 200X.
(12) Color spectrum: Spectrum analysis assisted to calculate era of porcelain.
(13) Fluorescent reflection: fluorescent reflection helps to distinguish between antique porcelain and new porcelain.
C. Shard appraisal and analysis by technical examination and library database
(13) Fluorescent reflection: fluorescent reflection helps to distinguish between antique porcelain and new porcelain.
C. Shard appraisal and analysis by technical examination and library database
(14) Clay
(15) Pigment
(16) Glaze Material
※ Element analysis was measured by Model JSM-6360 in the TA-I Technology Co., Ltd.
Conclusion：
Above are brief illustration of porcelain appraisal by dcl-CARD, whose antique appraisal requires not only visual appraisal but also scientific techniques. dcl-CARD is trying to build database system for comparing all the information. The more complete the database becomes, the more efficient antique appraisal reaches.
(15) Pigment
(16) Glaze Material
※ Element analysis was measured by Model JSM-6360 in the TA-I Technology Co., Ltd.
Conclusion：
Above are brief illustration of porcelain appraisal by dcl-CARD, whose antique appraisal requires not only visual appraisal but also scientific techniques. dcl-CARD is trying to build database system for comparing all the information. The more complete the database becomes, the more efficient antique appraisal reaches.
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