Mineralogical Characteristics and Colouration Mechanism of Blue Opals from Peru

Ying-ying XING; Li-jian QI; Hai-tao WANG

doi:10.15898/j.cnki.11-2131/td.201707250121

2017 Vol. 36, No. 6

Article Contents

Article navigation > Rock and Mineral Analysis > 2017 > 36(6): 608-613

Next Article Previous Article

Ying-ying XING, Li-jian QI, Hai-tao WANG. Mineralogical Characteristics and Colouration Mechanism of Blue Opals from Peru[J]. Rock and Mineral Analysis, 2017, 36(6): 608-613. doi: 10.15898/j.cnki.11-2131/td.201707250121

Citation:

Ying-ying XING, Li-jian QI, Hai-tao WANG. Mineralogical Characteristics and Colouration Mechanism of Blue Opals from Peru[J]. Rock and Mineral Analysis, 2017, 36(6): 608-613. doi: 10.15898/j.cnki.11-2131/td.201707250121

Mineralogical Characteristics and Colouration Mechanism of Blue Opals from Peru

1.
Gemmologocal Institute, Guangzhou College of South China University of Technology, Guangzhou 510800, China
2.
Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
3.
School of Ocean and Earth Sciences, Tongji University, Shanghai 200092, China

Received Date: 25 July 2017

Revised Date: 18 October 2017

Accepted Date: 24 October 2017

Abstract

Abstract

In recent years, the study of blue opal has been limited to the mineral composition and coloration mechanism. However, the chemical composition, infrared spectrum, and Raman spectrum of the blue opal have not been studied in details. Combined with previous research, Fourier Transform Infrared Spectroscopy (FTIS), X-ray Diffraction (XRD), Electron Microprobe Analyzer (EMPA), and UV Vis Absorption Spectroscopy (Uv-Vis) and Raman Spectroscopy were used to investigate vibration spectra, functional group characterization, mineral composition, and coloring mechanism of blue opal samples. Results show that the main mineral composition of blue opal is amorphous opal and the vibrational spectra show some peak frequency shifts relative to natural opal. EMPA shows that the main elements of blue opals are Si and Cu, whereas the Uv-Vis spectrum shows a broad band with higher absorption intensity near 742 nm. Combined EMPA and Uv-Vis spectrum results further indicate that the coloration element for the blue color of the opal is Cu, with the typical planar square structure of[Cu²⁺(H₂O)₄]²⁺. Moreover, the blue color and the Cu content are positively correlated, and with the increasing Cu content the blue color is more intense.
- Fourier Transform Infrared Spectroscopy /
- functional group /
- thermal variation behavior /
- blue opal

FullText(HTML)

References

[1]	Hyršl Dr J.Gemstones of Peru[J].The Journal of Ge-mmology, 2001, 27(6):328-334. doi: 10.15506/JoG.2001.27.6 CrossRef Google Scholar
[2]	Gaillou E, Fritsch E, Aguilar-Reyes B, et al.Common gem opal:An investigation of micro-to nano-structure[J].American Mineralogist, 2008, 93(11-12):1865-1873. doi: 10.2138/am.2008.2518 CrossRef Google Scholar
[3]	戴稚璇. 澳大利亚蓝色调欧泊的变彩效应与二氧化硅球粒间隙的关系[D]. 北京: 中国地质大学(北京), 2009: 1-10.http://d.wanfangdata.com.cn/Thesis_Y1783472.aspx Google Scholar Dai Z X.The Correlation between Play-of-Color Effect and SiO₂ Cavities Size of Australia Blue Opal[D].Beijing:China University of Geosciences(Beijing), 2009:1-10. Google Scholar
[4]	Franca C, Luigi M, Alberto L, et al.New physical, geo-chemical and gemological data of opals from Acari Mine (Arequipa Department, Peru)[J].Journal of Mineralogy and Geochemistry, 2015, 192(1):73-84. Google Scholar
[5]	亓利剑, 杨梅珍, 胡永兵, 等.秘鲁蓝欧泊[J].宝石和宝石学杂志, 2001, 3(3):13-16. Google Scholar Qi L J, Yang M Z, Hu Y B, et al.Blue opal from Peru[J].Journal of Gems and Gemmology, 2001, 3(3):13-16. Google Scholar
[6]	Fritsch E, Gaillou E, Ostroumov M, et al.Relationship be-tween nanostructure and optical absorption in fibrous pink opals from Mexico and Peru[J].European Journal of Mineralogy, 2004, 16(5):743-751. doi: 10.1127/0935-1221/2004/0016-0743 CrossRef Google Scholar
[7]	赵海平, 张雪梅, 何雪梅, 等.坦桑尼亚绿色蛋白石[J].宝石和宝石学杂志, 2014, 16(4):14-21. Google Scholar Zhao H P, Zhang X M, He X M, et al.Prase opal from Tanzania[J].Journal of Gems and Gemmology, 2014, 16(4):14-21. Google Scholar
[8]	Jia Y, Wang B M.Mineralogy and thermal analysis of natural Pozzolana opal shale with nano-pores[J].Journal of Wuhan University of Technology, 2017, 32(3):532-537. doi: 10.1007/s11595-017-1629-3 CrossRef Google Scholar
[9]	严俊, 胡丹静, 黄雪冰, 等.应用FTIR-SEM研究一类合成欧珀的微结构及其变彩成因机制[J].岩矿测试, 2017, 36(1):59-65. Google Scholar Yan J, Hu D J, Huang X B, et al.Investigation of the microstructure and play of color mechanism of a synthetic opal by FTIR-SEM[J].Rock and Mineral Analysis, 2017, 36(1):59-65. Google Scholar
[10]	严俊, 胡仙超, 方飚, 等.应用XRF-SEM-XRD-FTIR等分析测试技术研究丽水蓝色类欧泊(蛋白石)的矿物学与光学特征[J].岩矿测试, 2014, 33(6):795-801. Google Scholar Yan J, Hu X C, Fang B, et al.Study on the mineralogical and optical characteristics of blue opal from Lishui investigated by XRF-SEM-XRD-FTIR[J].Rock and Mineral Analysis, 2014, 33(6):795-801. Google Scholar
[11]	Smallwood A G, Thomas P S, Ray A S.Characterisation of sedimentary opals by Fourier transform Raman spectroscopy[J].Spectrochimica Acta:Part A, 1997, 53:2341-2345. doi: 10.1016/S1386-1425(97)00174-1 CrossRef Google Scholar
[12]	Sodo A, Municchia C A, Barucca S, et al.Raman, FT-IR and XRD investigation of natural opals[J].Journal of Raman Spectroscopy, 2016, 47(12):1444-1451. doi: 10.1002/jrs.v47.12 CrossRef Google Scholar
[13]	Nikbakht T, Kakuee O, Lamehi-Rachti M.Study of the ionoluminescence behavior of the gemstones:Beryl (aquamarinevariety), opal, and topaz[J].Journal of Luminescence, 2016, 171:154-158. doi: 10.1016/j.jlumin.2015.11.020 CrossRef Google Scholar
[14]	邹妤, 孙婉洁, 赵旭刚, 等.云南麻栗坡祖母绿生长环带特征[J].硅酸盐通报, 2017, 36(2):419-424. Google Scholar Zou S, Sun W J, Zhao X G, et al.Characteristics of growth zone of emerald from Malipo, Yunnan Province[J].Bulletin of The Chinese Ceramic Society, 2017, 36(2):419-424. Google Scholar