Revealing gemological features and artificial refinement of novel lavender amethyst

Abstract

With the growing demand for personalized and high-quality jewelry, the jewelry industry is continuously innovating to meet consumer needs. A new type of amethyst, called lavender amethyst, has emerged in the market in recent years. However, limited research has been conducted on this crystal, leaving gaps in our understanding of its gemological features, optical effects, source, and artificial refinement methods. The milky texture is the primary distinguishing feature of lavender amethyst. This study reveals that the milky appearance of lavender amethyst is caused by light scattering from silica spherules ranging from 20 to 50 nm in size. These spherules form during the recrystallization process near crystal defects, gradually accumulating silica and leaching onto larger defects during heat treatment. It is determined that existing lavender amethyst has been artificially optimized, with precise control of treatment temperature and heating time to achieve the desired milky white gradient. Effective transformation into lavender amethyst requires amethyst with sufficient crystal defects, exhibiting specific absorption peaks in the low-temperature infrared spectrum. This study provides a comprehensive analysis of the gemological features, optical effects, and artificial refinement of lavender amethyst, shedding light on its hazy appearance and offering insights for optimizing and controlling similar gem crystal structures.