摘要
目前市场上充斥着大量热处理刚玉,仅通过常规方法并不能科学分辨,为了准确判断刚玉是否经过热处理,需要对其谱学特征进行分析。首先对天然刚玉进行内含物观察,并测试记录他们的红外光谱、紫外吸收光谱,随后选取个别样品进行高温热处理,再对处理后的刚玉进行光谱测试,并与天然样品的光谱进行对比分析。结果表明:天然红宝石可检测到硬水铝石1 980和2 110cm-1的红外吸收峰,而热处理后由于高温破坏了AlO(OH)的结构,所以在热处理红宝石中此峰无法被检测;生长于还原条件下的碱性玄武岩型蓝宝石具有3 310cm-1处的红外吸收峰,经过1 600℃高温处理并恒温18h的热处理过程后,此峰消失。另外,经过热处理后,天然红宝石位于555nm左右的宽且强的吸收峰发生轻微偏移,且吸收峰更尖锐,波峰和波谷的吸收强度差增加。同样,对比天然和热处理蓝宝石,后者位于375,387,454nm处形成的吸收峰也更尖锐,吸收强度差值更大。上述这些变化可以帮助判断刚玉是否经过热处理。
Nowadays,agreat quantity of heat treating corundums are emerging in our market.It is hard to distinguish them scientifically just by conventional methods.In order to accurately determine whether the corundums have been heated or not,we need to analyse their spectral characteristics.This paper describes the spectroscopy identification of untreated and heated corundum.The experiment is conducted as follows：First,We observed the inclusions of corundum samples,then measured and recorded their infrared spectra,UV-Vis spectra by Fourier Transform Infrared Spectrometer and Ultraviolet-visible Spectrophotometer respectively.Next we chose a part of samples to heat,after the heat treatment,we recorded their spectra and made a comparison with that of untreated corundums.The results showed that we can detect the absorption peaks at 1 980 and 2 110cm-1 which represent diaspore in untreated ruby.However,after heat treatment,the absorption peaks disappear which means the structure of AlO（OH）has been destroyed.The sapphires which grown in alkali basalt under reductive condition appear the absorption peak at 3 310cm-1.However,this peak vanishes after 18 hheat treatment when the temperature is 1 600 ℃.For UV-Vis spectra of ruby,after heat treatment,the slight shift occurs in strong,wide absorption band at around 555 nm,and this band becomes more pointed.In addition,absorption intensity difference between wave crest and wave hollow increases.The absorption bands at 375,387,454 nm of heated sapphires are more pointed than that of the untreated sapphires,and absorption intensity difference rises.These changes in spectral characteristics can help us to distinguish untreated corundum from heat treating corundum.
作者
黄若然
尹作为
HUANG Ruo-ran YIN Zuo-wei(Gemological Institute, China University of Gesosciences（Wuhan）, Wuhan 430074, Chin)
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2017年第1期80-84,共5页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(41372224)
中国地质大学实验技术研究项目-重点项目(2013-23)
中国地质大学(武汉)珠宝检测技术创新中心项目资助
关键词
刚玉
天然与热处理
红外光谱
紫外-可见光谱
Corundum
Untreated and heat treatment
Infrared spectrum
UV-Vis spectrum
