1. Faculty of Gemmology and Materials, Hebei GEO University, Shijiazhuang 050031, China
2. Faculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, China
3. Qingdao Institute of Measurement Technology, Qingdao 266101, China
4. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences(Wuhan), Wuhan 430074, China
5. Hebei Key Laboratory of Green Development of Rock and Mineral Materials, Hebei GEO University, Shijiazhuang 050031, China
6. Engineering Research Center for Silicate Solid Waste Resource Utilization of Hebei Province, Shijiazhuang 050031, China
7. Gemstone Testing Center of Hebei GEO University, Shijiazhuang 050031, China
Abstract：Petroleum-bearing quartz crystals are rarely produced in nature.They are primarily produced in Pakistan, Madagascar, and Brazil. Due to liquid organic inclusions, it is highly sought after by the international mineral crystal collection market and researchers.In this study, we investigated the spectroscopic characteristics of petroleum-bearing quartz crystals recently discovered in Kunming Yunnan, which used laser Raman spectroscopy, gas chromatography-mass spectrometry, and photoluminescence spectroscopy. The findings indicated that the Kunming petroleum-bearing quartz crystals contain predominantly inclusions of brown-yellow liquid phase and black solid phase. The inclusions of the black solid phase exhibit yellow fluorescence under long-wave ultraviolet light, while the inclusions of the brown-yellow liquid phase exhibit blue-white fluorescence.TheRaman spectrum indicated that the primary component of the black solid inclusions is asphalt, with typical Raman peak shifts at 1 343, 1 606, 2 954, and 3 214 cm-1. The gas chromatography-mass spectrometry analysis revealed that the inclusions of brown-yellow liquid contain C9H20, C10H22, C12H26, and C13H28. The photoluminescence spectrum revealed that the asphalt of the solid phase exhibits photoluminescence peaks mainly at 512 nm, while the inclusions of the brown-yellow liquid phase exhibit photoluminescence peaks at 418, 441, 471 and, 505 nm. Based on the inclusions analysis, it is inferred that petroleum-bearing quartz crystals formed in hydrothermal crystal deposits of carbonate rock under low-temperature environments. The obtained composition and spectral characteristics are significant for studying the metallogenic geological environment of Kunming petroleum-bearing quartz crystals and exploring petroleum and gas resources in this area.
