Glaze Color Research Articles

Microstructural Study of the Coloring Variation of Chinese Sauce Glaze Replications

ABSTRACTSauce glazed wares of Yaozhou kilns are famous for their high gloss and distinctive glaze color palette varying from yellowish‐brown to reddish‐brown. In this work, sauce glazes were successfully replicated using the traditional technology of Yaozhou kilns. Micro‐Raman spectroscopy, combined with optical microscopy, scanning electron microscopy, x‐ray fluorescence, and reflective spectroscopy, was systematically applied to analyze the chemical composition, nature and distribution of crystals, and the coloration of the glazes. The results show that the yellowish‐brown glaze is mainly original from dendritic ε‐Fe2O3 crystals, whereas the reddish‐brown color is mainly derived from dendritic hematite crystals. Such dendritic structure could account for slightly color variations of the glaze surface observed in different angles, which also reported in Japanese Bizen ceramics. The principal component analysis (PCA) was further applied to study the Raman spectra of these iron oxides. The PCA results effectively indicates the structural disorders of these crystals introduced by ion substitutions. These substitutions could not only stabilize the crystals but also darken the crystals color. Besides, high Mg in the raw materials was found to benefit the growth of magnesioferrite crystals. The relative low level of Fe2O3, high level of SiO2, and CaO may relate to the formation of ε‐Fe2O3 crystals.

Study on the coloring mechanism of fireworks glaze of Lushan speckle porcelain from the Tang Dynasty

The fireworks glaze of Lushan speckle porcelain (618–907 A.D.) is a type of multicolored glaze that applies a surface-glaze (such as blue, gray-white glaze, etc.) on top of a black bottom-glaze. Its coloring mechanism was determined by using XRF, XPS, XRD, Raman, and SEM to study how its coloring was affected by its chemical composition, Fe valence state, crystal, phase-separated structure, and glaze flow. The results showed that the beige glaze was produced via oxidation and corrosion, and its color was mainly due to its high Fe3+ content and the gel layer. Dark blue and light blue glazes had a higher Fe2+/Fe3+ ratio, and the amorphous structure color of the dark blue glaze deepened its blue tone. A higher CaO content and droplet sedimentation made the dark blue glaze more fluid. The low miscibility between the surface-glaze and bottom-glaze and bubble movement made different-colored glazes merge to form fireworks patterns.

Influence of Ca3(PO4)2 on the Surface Morphology and Properties of a CaO-Al2O3-SiO2-Fe2O3-Based High Temperature Phase Reconstructed Complex.

In this study, a glaze slurry was prepared with different contents of tricalcium phosphate. It was then applied to a fly ash microcrystalline ceramic billet and sintered at 1180 °C for 30 min to prepare the complex. The aim was to obtain a high value-added application of fly ash in order to reduce environmental pollution. The study systematically investigated the influence of the Ca3(PO4)2 content on the crystal phase evolution, physical-mechanical properties, and micro-morphology of the complex. The results showed that products sintered at 1180 °C with 8 wt% Ca3(PO4)2 demonstrated better performance, with a water absorption of 0.03% and a Vickers microhardness of 6.5 GPa. Additionally, the study observed a strong correlation between the Ca3(PO4)2 content and the opacity effect. A feasible opacity mechanism was also proposed to explain the variation of glaze colors and patterns with different contents of Ca3(PO4)2.

Changsha ware glaze color: Composition, nanostructure, and copper and iron speciation

AbstractThe opacity/transparency, color, and production of designs in Changsha ware, a Tang dynasty Chinese stoneware renowned for its polychromy and pioneering high‐temperature red glaze, are studied by analyzing the composition, micro/nanostructure, and copper/iron speciation. The results shed new light on some of the most debated questions about Changsha ware. In particular, the role of glaze thickness, composition, and firing conditions on the coexistence of transparent and opaque glazes and of oxidized green and reduced red copper designs on the same object, and on the reason for the development of either green or turquoise colors. New data obtained by reproducing a copper red overglaze and underglaze painting with a similar glaze composition and thickness have provided new insights into the origin of the first high‐temperature copper reds and, in the absence of essential knowledge, their discontinuity. This study also contributes to the long debate regarding the use of overglaze versus underglaze painting techniques.

Formula process and coloring mechanism of bluish‐white porcelains from the Lanxi kiln in Fujian, China

AbstractBluish‐white porcelain was a prominent type of porcelain in ancient China, renowned for its distinctive artistic style and unique characteristics. The Lanxi kiln in Jianning County, Fujian Province, has unearthed a multitude of bluish‐white porcelain products from the Southern Song dynasty that exhibit vibrant glaze color and exceptional craftsmanship. The quality of these porcelains surpasses that of contemporaneous Jingdezhen and Baishe kiln products in Jiangxi Province, representing the pinnacle of bluish‐white porcelain excavated across various regions of China during the Southern Song dynasty. In this study, samples of bluish‐white porcelain from the Lanxi kiln and Baishe kiln, dating back to the Southern Song dynasty, were selected and analyzed via energy dispersive X‐ray fluorescence, ultraviolet–visible–near infrared (UV–Vis–NIR) spectrophotometer, metallographic microscopy, and scanning electron microscopy with EDS to investigate their glaze formula process and coloring mechanism. Moreover, these findings were subsequently compared with those of Jingdezhen bluish‐white porcelain from the same period. The results demonstrate that the raw materials of porcelain stones used in the glaze of the Lanxi and Jingdezhen kiln are similar in composition yet differ significantly from that employed in the Baishe kiln. Potassium feldspar was added to the glazes of the Baishe and Lanxi kiln, potentially existing exchanges of process of the two kilns due to their geographic proximity. The firing atmosphere of bluish‐white porcelain with different glaze colors in the same kiln exhibits significant variations. In particular, the lake blue sample undergoes firing under a strong reducing atmosphere, resulting in an excess content of Fe2+ in octahedral hexagon coordination within the glaze, thereby intensifying its blue hue. The colors of various glazes are determined by both chemical color and physical color. The former is a result of the absorption of Fe3+ in the ultraviolet region and the d‐d electron orbital transition of Fe2+ in the infrared region. However, the latter is not the scattering physical color but the diffuse reflection physical color produced by bubbles and anorthite crystallization layers.

Sustainable pink ink synthesis from calcium rich/eggshell waste: Chromium tin pink sphene

The chromium-doped tin sphene or malayaite (Ca(Sn,Cr)SiO5, PR233) was synthesized by solid-state reaction method at temperatures between 1300 and 1500 °C. Two different pigments were obtained according to the chemical formula CaSn(1-x)SiCrxO5±δ (x = 0.01 and 0.03). Eggshell, calcium-rich wastes (CRW), were utilized as raw material. The eggshell was only washed and milled. In the pigment reactant formula, more than 30% by weight of CRW was used. Pigments were milled by a planetary ball mill with zirconium oxide equipment. The pigments obtained were used as glaze colorants and inks by reducing the particles to micro and nano sizes, respectively. The Dv(90) of pigments milled for glaze application is 7.19–7.98 μm, while it is 660–678 nm for ink application. Micron-sized pigments were mixed with transparent glaze and applied to the engobe-coated ceramic tile with a pool-type film applicator. The inks were applied to engobe-coated and transparent glazed ceramics through the screen printing method. After glaze and ink application, ceramic tiles were fired at 1130 °C. When the color values of glaze application are examined, the values for L*, a* and b* are between 48.9 and 63.8, 18.4–23.5, 1.2–4.6, respectively. In the Ink application, L*, a* and b* are 71.0–81.2, 21.8–12.7 and 0.9–2.8, respectively. Characterization was performed using various devices such as X-ray diffraction (XRD), X-ray fluorescence (XRF), field emission-scanning electron microscopy (FE-SEM), and spectrophotometer. The conducted studies revealed that the calcium requirement for Ca(Sn,Cr)SiO5 pigment was entirely met using CRW, and a ceramic ink suitable for inkjet applications was successfully obtained.

The effect of composition and holding time on glaze production using basalt rock as a base

This research studied the potential use of local basalt and feldspar from Lampung Province, Indonesia, as glaze materials. Frit(s) are composed of changing basalt-to-feldspar weight ratios of A (30:70), B (50:50), C (70:30), and D (100:0) w/w%. The added 20% boric acid to the total weight reduces the process temperature to 1,000oC with holding times of 1, 4, and 8 hr(s). Based on the chemical composition test of the specimen, the four variations of the sample have SiO2 content above 40%, and the average SiO2/Al2O3 ratio is 4 and 5, which is usually a low-alumina glaze that will cause a glossy effect and have an amorphous structure. At point 2theta 29o, amorphous forms. Quartz (SiO2), albite (NaAlSi3O8), anorthite (CaAl2Si2O8), and coesite (SiO2) phases were discovered in the glaze specimens. The anorthite phase in glass-ceramic glaze gives a transparent glaze color due to the amorphous glassy phase formed during heat treatment. The findings of this study suggest that local materials based on basalt and feldspar may be used as glaze materials to provide a smooth texture and surface; the glaze layer is evenly distributed, can follow the full surface contour of the test specimen, and has low porosity.

Study on the coupling effect of chemical color and structural color for Lushan speckle porcelain glaze in the Tang Dynasty (618-907 A.D.)

The Lushan speckle porcelain glaze with charming color fired in the Tang Dynasty (618-907A.D.), is the earliest high-temperature kiln-changed glaze. To clarify its coloring mechanism, the correlation among composition, microstructure and visual appearance of the shards excavated from Lushan kiln site was investigated by XRF, XPS, SEM and TEM. The results indicated that the coloring of sky-blue or moon-white opalescence glaze of the Lushan speckle porcelain was the combination of the chemical color of iron ions and the structural color formed by the coherent scattering of phase-separated droplets. The high atomic ratio of Fe2+/Fe3+ and the small average diameter of phase-separated droplets were beneficial for the formation of the blue opalescence with high color saturation. In addition, it was precisely the presence of black bottom-glaze that incoherent scattering light was greatly absorbed, leading to a higher contrast and a more pronounced structural color of the opalescence glaze.

Comparative study on the Ru ware, Ru-type ware of Qingliangsi kiln and celadon of Zhanggongxiang kiln.

Thirty-three porcelain shards (28 Ru ware and 5 Ru-type ware) unearthed from Qinglingsi kiln and 31 celadon fragments from Zhanggongxiang kiln were studied systematically for tracing their correlation and difference in glaze and body characteristics through a variety of characterisation methods. Samples without HF corrosion were applied to achieve the microstructure and composition details by SEM and TEM. Results exhibited that there were certain similarities between Ru ware, Ru-type ware and Zhanggongxiang kiln celadon in glaze colour and thickness, body features, fracture structure; however, they showed obvious differences in body thickness, chemical composition of glaze and body, phase constituents and microstructure of glaze. Plentiful needle-like diopside were widely distributed in Zhanggongxiang kiln celadon glazes, while this type of crystals was only existed in few Ru and Ru-type ware glazes with small content. Besides, a large amount of residual quartz was present over the Ru ware glazes, which could have relation to the incorporation of agate. The liquid-liquid phase separation structure (Ca-rich droplets and Si-rich matrix) was generated within the interspaces of anorthite clusters or around the brims of anorthite needles or columns. The occurrence of phase separation was generally accompanied by Al2 O3 consumption, but suppressed in the areas far from anorthite due to the rise of Al2 O3 content, indicating that Al2 O3 was the most sensitive constituent for this glaze behaviour. The distinguished size, shape and distribution of phase-separated droplets or interconnected structures were closely associated with the scale and crowding level of anorthite crystallisation.

Lagrange-enhanced GRA method for probabilistic simplified neutrosophic MADM: Yaozhou porcelain decoration design quality evaluation

Yaozhou ware is located in Huangbao Town, Tongchuan City. It began in the Song Dynasty and flourished in the Tang Dynasty. Its warm and jade like glaze color, exquisite decorative techniques, and rich and varied utensil shapes all give it a very important position in history. The traditional Yaozhou porcelain contains the ancient people’s concept of creation and their attitude towards humans and nature. Each artifact of Yaozhou porcelain contains the designer’s understanding and emotions about the world, establishing a dialogue between people and objects to form a desired lifestyle. The production method of Yaozhou porcelain that has been preserved for thousands of years shares many similarities with modern design ideas. The quality evaluation of Yaozhou porcelain decoration design is viewed as multiple-attribute decision-making (MADM). The grey relational analysis (GRA) is a useful tool to cope with the MADM issue. The probabilistic simplified Neutrosophic set (PSNSs) is easy to characterize uncertain information during the quality evaluation of Yaozhou porcelain decoration design. In this paper, in order to obtain the weight information, an optimization model is constructed to obtain a simple and exact formula which can be employed to derive the attribute weights values based on the Lagrange function and the probabilistic simplified neutrosophic (PSN) grey relational analysis (PSN-GRA) method is originated for MADM to rank the decision alternatives. Finally, a numerical example for quality evaluation of Yaozhou porcelain decoration design is used to verify the practicability of the PSN-GRA method and compares it with other methods.

Integrating typological and stylistic characteristics with scientific results on the provenance study of of proto-porcelain from the Yejiashan Cemetery dating to the early western Zhou Dynasty

There has been widespread concern about the provenance of proto-porcelain in previous studies, which is fundamental in determining the origin of porcelain. However, there are still different opinions on the provenance of proto-porcelain. To discuss this question, this study analyzed 21 proto-porcelain shards, excavated from the Yejiashan Cemetery, on the basis of typology, petrography, and LA-ICP-AES methodologies. Three shards from the Panlongcheng site were also collected for comparative analysis. The typological analysis showed that the majority of proto-porcelain samples from the Yejiashan Cemetery were similar to those from Northern China in type, shape, decoration,and glaze color, while 2 shards showed typical Southern characteristics. The petrographic analysis indicated that there were two different patterns of distribution for quartz particles in the collected samples, which suggested the potential existence of at least two different origins. The LA-ICP-AES analysis results also supported two different origins for Yejiashan proto-porcelain and suggested that one may originate from Zhejiang Province in Southern China. In summary, our study has demonstrated the existence of at least two distinct provenance areas for the proto-porcelain sourced from the Yejiashan cemetery. This distinction is founded upon disparities in typological characteristics, distribution patterns of quartz particles, and chemical compositions. This conclusion contributes to a better understanding of cultural exchange between the Zeng state and neighboring regions and can shed light on the manufacturing industry of the early Western Zhou Dynasty (1046–771 BC).

Study on the English Translation of the Names of Ceramic Artifacts in Museums

By analyzing the structure and language characteristics of the names of ceramic exhibits in the collection, this paper puts forward the main points of translation and the corresponding translation methods, further analyzes the components of the names of porcelain from the perspective of glaze color, shape, decoration, place of origin, age and other aspects. The purpose of this study is to standardize the translation of the names of ceramic artifacts in the museum’s collection, and to improve the appreciation and awareness of the museum’s porcelain among international tourists.

Technological Analysis of Glazed Tiles Unearthed from Bao’ensi in Nanjing

To understand the firing technology and the level of production of glazed tiles in the Ming Dynasty, an ultraviolet-visible-near-infrared (UV-vis-NIR) spectrophotometer and an energy-dispersive X-ray fluorescence (XRF) spectrometer were used to systematically analyze the glaze color and chemical composition of glazed tiles unearthed from the southern area of the Bao’ensi site. The results revealed that little difference exists in the main wavelengths of the same glazed tile samples, but that the colored elements of glaze with different colors are different. Iron (Fe) is the main element that affects the color of yellow glaze; copper (Cu) is the main element that affects the color of green glaze; and the main colorants that affect the color of black glaze are Fe, Cu, and manganese (Mn). The yellow and black glaze unearthed from the southern area of the Bao’ensi site were relatively mature in terms of raw material composition and technological formula, whereas the raw material and technological formula of green glaze were not stable enough. To meet temple construction needs, workers were skilled in firing glazed tiles with different glaze color requirements, indicating that the glaze color of the glazed tiles was relatively mature at that time.

SrMn1-xFexO3-δ (x = 0–1) black ceramic pigment: Synthesis, color properties, and application

In this work, SrMn1-xFexO3-δ (x = 0–1) black ceramic pigments were synthesized by the solid-state method. The research explores the influence of calcination temperature and iron ion doping on the color properties of the pigments. Furthermore, the potential applications of SrMn1-xFexO3-δ pigments in ceramic glaze and heat-absorbing materials are also discussed. The findings reveal that the synthesized SrMnO3 pigment exhibits the lowest L*-value (22.30) at 1100 °C, although it displays a slight blue hue. To optimize the color properties of the SrMnO3 pigment, iron ion doping is employed. When the doping level of iron ions is 50 mol.% (i.e., x = 0.5), the L*-value of the SrMn0.5Fe0.5O3-δ pigment calcined at 1000 °C significantly decreases to 19.77, while the a*- and b*-values approach 0, resulting in a pure black color. This is attributed to the high surface roughness, low band gap energy, and substantial oxygen vacancies present in the SrMn0.5Fe0.5O3-δ pigment. The tinting mechanism of the SrMn1-xFexO3-δ pigment in the ceramic glaze is classified as "ion tinting", wherein the glaze color relies on the concentrations of Mn and Fe ions. When the pigment content reaches 36 wt%, the L*-value of the glaze drops to 4.94, showing a deep black shade. Additionally, the SrMn0.5Fe0.5O3-δ pigment exhibits excellent sunlight absorption capabilities, with a near-infrared reflectance (R*) of only 5.04%. This research presents a black ceramic pigment with various advantages, such as simplified processing, affordability, environmental friendliness, and exceptional color performance.

Evaluation of the Vickers hardness on denture acrylic resins by glaze color

Evaluation of the Vickers hardness on denture acrylic resins by glaze color

Study on the coloring mechanism of Longquan light greenish-blue celadon glaze from the Southern Song and Yuan Dynasties

To study the coloring mechanism of the light greenish-blue glaze used in celadon shards from the Longquan kiln from the Southern Song and Yuan Dynasties, celadon samples were analyzed using colorimetry, XRF, XRD, XPS, and SEM/EDS. The results showed that the a* and b* values of the light greenish-blue celadon glaze from the Southern Song and Yuan Dynasties were smaller than those of the celadon glazes from the Ming Dynasty, while the value of L* value from the Southern Song and Yuan Dynasties was larger than that from the Ming Dynasty. The opaque and jade-like appearance of the light greenish-blue celadon was mainly caused by the effect of light on small and dense air bubbles and the large number of quartz crystals in the glaze. Fe2O3 dominated the color of Longquan celadon, and the ratio of Fe2+ to Fe3+ in the light greenish-blue celadon glaze from the Southern Song and Yuan Dynasties was higher than that of the celadon from the Ming Dynasty. This was the major reason why the light greenish-blue celadon from the Southern Song and Yuan Dynasties was bluish and why celadon from the Ming Dynasty was yellowish-green. However, the phase-separated structural color had little influence on the color of the light greenish-blue glaze in the Longquan kiln from the two dynasties. The color of the celadon from the Southern Song and Yuan Dynasties was mainly chemical in nature.

Express Assessment Method for Color Characteristics of Cocoa-Containing Food Systems

In the contemporary context, climatic conditions in cocoa bean-producing countries and disrupted logistics chains due to the coronavirus pandemic complicate stable cocoa products supply. The study aimed at developing an express assessment method for color characteristics of cocoa-containing food systems where cocoa powder replaced with brown pigment melanin obtained from buckwheat husks, partially. A man prepared five confectionery glaze prototypes: one based on non-alkalized cocoa powder and four samples containing 3; 5; 7 and 10 % melanin powder as a substitute for cocoa powder. The confectionery glaze based on alkalized cocoa powder served as a comparison sample. To study the glaze color characteristics, the researchers covered white plates with samples, enabled the glaze to harden, and then, took images of the glaze surface using a digital camera in a white box at a color temperature of 6000 K; processed images using image analysis software that provided color coordinates determination of any point of the uploaded image in the RGB model. Then, a man determined the color coordinates in trichromatic XYZ coordinates using a color converter. The results revealed that the confectionery glaze prototype containing 15% non-alkalized cocoa powder and 10% melanin was close to the control sample in terms of color characteristics. The suggested approach advantages are the expensive equipment absence, simplicity and data processing accessibility. The method enables running an objective color assessment of a cocoa-containing product, comparing product samples with each other, and defining color differences. The research results offer the challenges for the color scales development for cocoa-containing foods quality assessment.

Study on additives assisted reduction of celadons

Celadons were prepared in the reducing atmosphere with purple clay and other natural elements. Different concentrations of silicon powder, silicon carbide, and tin dioxide were used as auxiliary reducing agents to investigate their effects on celadons. The results showed that the brightness value of celadons increased and subsequently declined when Si and SiC were introduced, and the glaze color gradually shifted from yellowish-green to bluish-green. On the other hand, samples with SnO2 had an opaque yellowish-green tint. According to XPS data, the reducing ability of SiC was added, followed by Si and SnO2. The structural colors of samples containing Si, SnO2, and without reducing agents were weak. Otherwise, celadons with SiC could yield blue structural colors conforming to the “Rayleigh scattering” effect. In conclusion, the reducing atmosphere raised the quantity of Fe2+ in celadons, resulting in blue colors, and additives created a variety of chemical and structural color coupling effects, leading to different aesthetic effects.

Influence of the thickness of the copper glaze layer on the color and its formation mechanism

In this paper, the effects of glaze layer thickness on the color properties of copper glaze were investigated, and the related mechanism was also revealed. The results manifest that the glaze thickness would affect the color of copper glaze. The color properties of copper glaze are determined by the phase-separated structure, the distribution of elements and the valence state of copper species. Due to the heterogeneous distribution behavior of the elements, the copper glazes with all thicknesses have three phase-separated structures, which are spherical (top layer), worm-like (interlayer) and nano-porous network-like (bottom layer). Simultaneously, the copper glazes with all thicknesses have three colors, of which the bottom layer of all samples is red. However, the color of the top layer gradually changes from milk white (0.2 mm) to cyan (0.4–0.6 mm) and then to blue (0.8–1.0 mm) with the green body thickness increases. The color of interlayer is the result of the color mixing of the top and bottom layer. A thicker green body thickness (>1 mm) could be propitious for copper glaze to present a superior color performance. This work provides a new and an easily overlooked perspective for the investigation of copper glaze.

Sırlı Tütün Lüleleri

Since the mid-19th century, tobacco pipes have been one of the subjects that attracted the attention of researchers. These studies generally focus on the clay structures, clay and coating colors, types and ornamentations of the pipes, however no studies have been carried out directly on the glazed pipes. 
 Glazed pipes are produced in two styles, Western and Eastern style pipe. It has been applied to the types produced with and without heels of Western style examples. In the Eastern style examples, besides the different types of bowls such as flattened round bowls, cylindrical bowls and tulip bowls, there are also special examples that go beyond the general types, such as in the form of shoes. The use of glaze can be seen both in the two-part mold making pipes and the pipes produced using the potter’s wheel. Glazed pipes are made of grey and kaolin clay or red clay. There is diversity in glaze colors. Light or dark green, opaque white, light or dark yellow, black and brown glazed samples of glazed pipes are found. Its visuality sometimes has been increased with herbal, geometric, figured or written ornaments applied to glazed bowls.
 As a result, while samples of Eastern style glazed pipes can be found especially in Ottoman area; one-piece pipes are mostly encountered in Central Europe. In this context, it is determined that the spreading area of three-part glazed pipes are wider than the one-piece ones. Eastern style glazed pipes may have affected Western style pipe or both types may have been influenced by each other.