Xue Zhiyu, Zhang Sixue, Guo Qingfeng, Yang Biao, Liao Libing
School of Gemmology, China University of Geosciences Beijing 100083 China
Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Sciences and Technology, China University of Geosciences Beijing 100083 China
RSC Adv. 2025 Aug 19;15(36):29311-29322. doi: 10.1039/d5ra04044b. eCollection 2025 Aug 18.
Spodumene, a lithium-rich pyroxene mineral, exhibits a wide range of colors and distinctive luminescent properties, yet the mechanisms underlying its coloration and fluorescence remain incompletely understood. In this study, twelve natural spodumene samples of varying colors (purple, yellow, green, and nearly colorless) were systematically analyzed by modern testing technology. Color variation of the sample is primarily controlled by the Mn/Fe ratio, with purple tones corresponding to Mn/Fe > 1, yellow to green to Mn/Fe < 1, and colorless samples showing negligible Mn and Fe content. All samples exhibited two emission centers near 420 nm and 600 nm, attributed to lattice defects and the T(4G) → A(6S) transition of Mn, respectively. The 600 nm emission band is responsible for the observed orange-red fluorescence under long-wave UV light. Fluorescence intensity was negatively correlated with Fe content, and fluorescence lifetimes at 600 nm increased with Mn concentration, reaching approximately 4000 μs in Mn-rich samples. These findings not only clarify the synergistic role of lattice defects, Mn activators, and Fe quenchers in controlling the coloration and luminescence mechanisms of spodumene, but also offer a scientific foundation for engineering synthetic luminescent materials with targeted chromatic properties and for gemological enhancement strategies.
锂辉石是一种富含锂的辉石矿物，呈现出广泛的颜色和独特的发光特性，但其呈色和荧光的潜在机制仍未完全了解。在本研究中，利用现代测试技术对十二个不同颜色（紫色、黄色、绿色和近无色）的天然锂辉石样品进行了系统分析。样品的颜色变化主要受锰/铁比例控制，紫色调对应锰/铁>1，黄色到绿色对应锰/铁<1，无色样品的锰和铁含量可忽略不计。所有样品在420nm和600nm附近均表现出两个发射中心，分别归因于晶格缺陷和锰的T(4G)→A(6S)跃迁。600nm发射带是在长波紫外光下观察到的橙红色荧光的原因。荧光强度与铁含量呈负相关，600nm处的荧光寿命随锰浓度增加，在富锰样品中达到约4000μs。这些发现不仅阐明了晶格缺陷、锰激活剂和铁猝灭剂在控制锂辉石呈色和发光机制中的协同作用，也为设计具有目标颜色特性的合成发光材料和宝石学增强策略提供了科学依据。
