Mineralogical Characteristics and Luminescent Properties of Natural Fluorite with Three Different Colors

Abstract

Fluorite is rich in mineral resources and its gorgeous colors and excellent luminescence characteristics have attracted the attention of many scholars. In this paper, the composition, structure, luminescent properties, and the potential application value of three fluorites with different colors and are systematically analyzed. The results show that REE and radioactive elements have effects on the structure, color, and luminescence of fluorite. Radioactive elements Th and U will aggravate the formation of crystal defects in fluorite. The green color is related to Ce3+ and Sm2+. Colloidal calcium and F− center are responsible for the blue-purple color of fluorite. There are many luminescent centers, such as Eu, Pr, Dy, Tb, Er, and Sm, in fluorite. The blue fluorescence is mainly caused by 4f7-4f65d1 of Eu2+. In addition, it is found that fluorite has certain temperature sensing properties in the temperature range of 303–343 K.

Analyzing Optical Properties of Natural Fluorite Crystals: A Comprehensive Investigation

“…3. In this gure, a distinctive Raman peak is consistently observed for all samples from different areas, appearing at approximately 322 cm ¹ [17]. This observation aligns with the uorite peak documented in the RRUFF database (ID: R050046).…”

“…Lewandowski et al [21] observed Raman peak at 319.13 cm − 1 for calcium uoride. This speci c peak at around 320-322 cm ¹ is attributed to the T 2g Raman active vibrational mode of uorite [17], [22][23][24][25][26]. It's worth noting that white uorite typically exhibits a single Raman peak at around 320 cm ¹, while non-white uorite may display additional peaks at different locations [19].…”

“…Aimacaña et al [43] conducted Diffuse Re ectance UV-Vis spectroscopy on part-CaF 2 powder to analyze its optical characteristics. Ge et al [17] examined the UV-visible spectra of three uorite samples with different colors.…”