• Journal of Conservation Science
• /
• v.25 no.3
• /
• pp.335-345
• /
• 2009

This paper presents investigations on 60 glass beads excavated from floorless tombs of Eunpyeong Newtown site to figure out composition and lead isotope ratio by SEM-EDS and TIMS, which show the difference between their compositions and Pb provenance of lead glass. The results of the composition analysis are that excavated glass are mainly divided into Potash glass($K_2O$-CaO-$SiO_2$) and Potash-lead glass($K_2O$-PbO-$SiO_2$) and the samples excavated from III-3 floorless tombs No.1005 are presumed not glass but Quartz. The transparent 9 lead glasses excavated from II-3 floorless tomb No.101 and III-3 floorless tomb No.908 seem to be manufactured by the same raw material at same site because the concentration of their compositions are well accorded with each other and deviations of them are very limited. As a result of principal component analysis(PCA), glass beads excavated are largely assort to two groups, Potash glass and Potash lead glass as well. That is, glass beads excavated from Eunpyeoung Newtown sites are quite different two types of main composition. In addition, the results of Pb provenance analysis used in lead glass confirm that most lead glass are significantly correlated with galena of northern China.

• Conservation and Restoration of Cultural Heritage
• /
• v.1 no.1
• /
• pp.3-8
• /
• 2012

Chemical compositions and lead isotope ratios for four glass bead samples of Seokga-tap were analyzed and the results were organized. Among 4 glass beads found in the Seokga-tap, 3 pieces were lead glass. Manufacturing method was to firstly grind pebbles finely and mix lead ore to be melt at $740{\sim}760^{\circ}C$. The mixed ratio of silica and lead was 3:7. Moreover, The evaluation on the lead isotope ratio indicated that two lead glass pieces used lead ore from northern Korea. One piece has the direction of southern Korea lead ore, but it requires a further review. One glass bead of Seokga-tap was brown and it was potash lead glass ($K_2O-PbO-SiO_2$) System. The mixed ratio was approximately 50:10:40 for silica, natural saltpeter, and lead, respectively. Lead isotope ratio data fell within the lead ore from northern China. Therefore, it was concluded that potash lead glass found in the Seokga-tap was produced in northern area of China at the end of $10^{th}$ century and transferred to the Seokga-tap.

• Journal of Conservation Science
• /
• v.28 no.3
• /
• pp.205-216
• /
• 2012

65 samples of glass bead excavated from Mahan tombs of Asan Bakjimeure site consists of 13 of potash glass group and 52 of soda glass group and soda glass is superior in numbers. When classified according to color, purple blue glass bead is accompanied potash and soda glass group whereas purple glass bead is potash glass group and red, greenish blue, green and gold foil glass bead is soda glass group. Purple blue glass bead is classified as LCA type in which the content of the stabilizer is low. Of this, the soda glass categorized as LMK type with low content of MgO and $K_2O$ is determined that natron is used as the raw material. As to red glass, the homogeneous glass is LCA-B/HMK type and the heterogeneous glass is HCLA/LMK type. Thus, each of these two types are likely to be used plant ash and natron respectively. Greenish blue and green glass depends of the type that round glass is LCA-A/LMHK type and the segmented glass is LCA-B/HMK type. The gold foil glass bead is manufactured by the purity of 19.9~22.6K gold foil and the soda glass of HCLA/LMK type. In other words, the most of the glass bead of Asan Bakjimeure site is similar to the composition of the glass confirmed in other sites of the Baekche period. On the other hand, the greenish blue and green segmented bead and some red round bead is a different chemical composition is considered that the difference in raw materials. These characteristics is expected to be an important evidence for the understanding of the trade system of the ancient glass.

• 보존과학연구
• /
• s.32
• /
• pp.113-121
• /
• 2011

Four glass beads from Hakso-ri site, O'chang were analyzed for thirteen oxides with SEM/EDS and lead isotope ratios with TIMS respectively. These samples were classified to potash glass system($K_2O-CaO-SiO_2$) with HCLA(High CaO, Low $Al_2O_3$). However three samples with above 4% for lead could be classified to potash-lead ($K_2O-PbO-CaO-SiO_2$)glass system and it seemed that coloring agent for greenish blue was Cu. Lead isotope ratio data for four samples did not make a group but scattered to the space respectively. It needs more study for compositions and lead iosotope data of potash-lead glasses with regions and ages.

• Journal of Conservation Science
• /
• v.16 s.16
• /
• pp.104-109
• /
• 2004

The characteristics and composition of the ancient glasses excavated at Songdong-ri, Sangju, Kyongsangbuk-do were analyzed using Scanning Electron Microscope attached with Energy Dispersive Spectrometer. As the results, the glass beads of Songdong-ri showed that there were changed the composition, the color and types according to the periods. There were appeared potash and soda glass group at A.D.4 century and potash and mixed alkali glass group at A.D. 17 century. The potash glasses of A.D. 4c. were colored blue and contained low $Al_2O_3$ and CaO composition as below $5\%$. The soda glasses of This period were colored blue and red, and contained $Al_2O_3$ composition as upper $5\%$. But the potash glasses of A.D.17c. showed the transparent yellow color and considerably higher CaO, $11.7\%$. 'Coil glasses' typed unique were colored yellow-brown, Cu-blue and colorless, were classified the mixed alkali glass as upper $5\%\;of\;Na_2O\;and\;K_2O$. The composition of coil glasses were presented first at this study.

• Conservation Science in Museum
• /
• v.13
• /
• pp.45-49
• /
• 2012

A scientific analysis was carried out on the 14 pieces of glass beads excavated from the Daho-ri site NO. 6, Changweon. Most of the glass pieces were made of light blue transparent glass with round bubbles aligned in a regular direction. As a result of the SEM-EDS analysis, all the glass pieces turned out to be within the potash glass group (K₂O-SiO₂) and were identified to be the LCA (Low CaO, Low Al₂O₃) series glass, of which the concentration is 5% or below for CaO and Al₂O₃ respectively. In addition, it is presumed that plant materials were refined or a mineral (saltpetre, KNO₃) was used as the raw materials for making potash and also that the ingredient acting as a colorants for light blue color was affected deeply by CuO.

• Journal of Conservation Science
• /
• v.31 no.3
• /
• pp.255-265
• /
• 2015

In this study, the potash glass beads of 281 samples in 30 sites analyzed until now were classified according to the chemical composition. And the color, size, manufacturing technique and distribution period were compared. Korea potash glass beads are divided into 3 types depending on the stabilizer content. I, II type is the CaO and $Al_2O_3$ content of less than 5%. Relatively, I type has a high CaO and II type has a high $Al_2O_3$. In contrast, III type comprises more than CaO 5%. I, II type is the saltpetre, III type is estimated using plant ash as row material of flux. A review of the properties by type, I type is cobalt blue, copper blue and purple beads. The outer diameter is sized to the range 1.4~7.4mm. Also it was produced by the drawing technique. It was used continuously from BC 1C until around AD 6C. On the other hand, II type is outer diameter of 1.9~3.6mm and a copper blue beads. manufacturing technique is the same as the I type. This seems to have been in use since around AD 1C to 4C. Finally, III type is brown, colorless, amber beads and an outer diameter of about 10mm. It was formed by winding technique and appeared in the tombs of Goryeo and Joseon Dynasty. As a result, 3 types of potash glass beads distributed in Korea is likely to flowing through the various trade routes from different provenances.

• Conservation Science in Museum
• /
• v.30
• /
• pp.71-88
• /
• 2023

This paper examined the visible characteristics and chemical composition of glass beads from the Joseon Dynasty as well as the associations thereof. It also explored the characteristics and uses of glass beads by region. This study covered a total of 1,819 pieces excavated from 25 locations in the Gyeonggi, Chungcheong, and Gyeongsang regions, of which 537 pieces were analyzed for their chemical composition. Glass beads of the Joseon Dynasty take a variety of shapes such as a Round, Coil, Floral, Segmented, Flat, Oval, and Calabash. Colors vary from shades of brown (brown, lemon yellow) and shades of blue (Bluish-Green, greenish-Blue, Purple-Blue) to shades of white (colorless, white) and shades of green (Green, Greenish-Blue, Greenish-Brown). Brown accounts for the largest percentage, followed by Bluish-Green, greenish-Blue. It was identified that Drawing technique was the most common glass bead production technique of the Joseon Dynasty. Potassium oxide (K₂O) was the most common flux agent for glass beads, while the potash glass and mixed alkali glass groups account for the largest quantity. The choice of stabilizers depended on the type of flux agents used, but the most common were calcium oxide (CaO) and aluminum oxide (Al₂O₃). The potash glass and potash lead glass groups are high in CaO and low in Al₂O₃, the mixed alkali glass group is high in CaO, and the lead glass group is low in CaO. In terms of the association between color and shape, most of the beads with shade of brown and blue have round shapes of brown and blue have spherical shapes, while the coil shape is prominent in blue beads. A high percentage of green and colorless beads also take the shape of a coil, while white beads in general have a floral shape. In terms of the association between shape and chemical composition, round, floral and segmented shapes account for a high percentage of the potash glass group, while coil and flat shapes are common in the mixed alkali glass group. This paper also analyzed the colorants for each color based on the association between color and chemical composition. Iron (Fe) was used as the colorant for brown and white, and titanium (Ti) and iron were used for light yellow. Purple-Blue was produced by by cobalt (Co), and greenish-Blue, Bluish-Green, green, Greenish-Blue were produced by iron and copper (Cu). Colorless beads had a generally low colorant content.

• Journal of Conservation Science
• /
• v.32 no.1
• /
• pp.63-73
• /
• 2016

This study defined material and characteristics of 24 glass fragments and 26 whole glass beads. The feature of glass beads shape are divided into 5 types following color, size, weathering condition and manufacturing techniques. Through the chemical composition, the first and second type is soda glass, the third type is potash glass, the fourth and fifth type is lead barium glass. This site showed the aspect that the chemical composition is changed according to the feature of glass shape and was found that various chemical compositions. Looking at the flow of glass culture, the tomb that are lead barium glass IItype and potash glass I, IItype is relatively preceding period and the tomb that are soda glass and lead barium glass IIItype is following period.

• Conservation Science in Museum
• /
• v.31
• /
• pp.21-37
• /
• 2024

This paper sought to garner an understanding of Daegaya glass culture by observing the micro-structure and analyzing the chemical composition of 43 glass beads excavated from the No.73 and 74 ancient tombs in Jisan-dong, Goryeong, which are estimated to have a central age of 5th century CE. The visible characteristics and micro-structure of these artifacts were observed with a optical microscope and an scanning electron microscope, while their chemical composition was analyzed with an energy-dispersing spectrometer attached to the scanning electron microscope. As a result, the glass beads of Jisan-dong, Goryeong were identified to have been formed using various methods such as drawing, casting, and folding techniques, with the majority molded by the drawing technique. In terms of chemical composition, 32.6% were in the potash glass group and 67.4% in the soda glass group, with the latter divided into various fluxes such as high alumina glass, netron glass, and plant ash glass. Compared to Baekje's cultural region in the same age, the composition of these ancient glass artifacts demonstrates a high share of the potash glass group. This shows that, despite the shift from the potash glass group to the soda glass group in ancient Korean glass culture, glass composition differs from region to region or depending on the cultural sphere of influence. In the soda glass group, high-alumina glass comprised 23.3%, natron glass 43.0%, and plant ash glass was 1.2%. Among them, the main type of Korean soda glass is high-alumina glass, as natron glass and plant ash glass are known to have appeared later, but the results of scientific analysis of the glass beads excavated in Jisan-dong can be expected to provide important clues about the inflow and transformation of ancient glass on the Korean Peninsula. In the No. 73, 74, and 74-1 ancient tombs, which were found to have been built in chronological order by the excavation survey, the glass beads showed only slight variations depending on their production period. Nonetheless, the chemical composition of glass is deemed to have a close correlation to color.