Phase transformations as important markers for heat treatment detection in corundum and other gemstones
Detection of heat treatment of ruby and sapphire and other colour varieties of corundum is a major issue for the trade and laboratories alike. Heat treatment of corundum is commonl
A Review and Synthesis of the Geology and Gem Resources of Granitic Pegmatites in Southern California, USA
Gem-bearing pegmatites in Southern California are hosted by the Peninsular Ranges batholith, and occur in ten districts in San Diego and Riverside counties (Figure 1a and Table 1).
Mechanism and Application of High-Temperature Copper Diffusion in Surface Recoloring of Labradorites
Feldspar, with the chemical formula of [KAlSi3 O8 ]x[NaAlSi3 O8 ]y[CaAl2 Si2 O8 ]z (x + y + z = 100), is one of the most important rock-forming minerals in the earth’s crust, and
Quantitative estimation of spinel’s thermal and geothermal history by photoluminescence spectroscopy and its application in spinel origin determination
The thermal history of spinel can not only be used to distinguish the natural spinel from heated and synthetic ones, but also to reveal that the spinel underwent different geologic
Cobalt spinel from Bai Buoi mine, Yen Bai, Vietnam
The cobalt bearing spinel from Lukande, Tanzania, discovered in 2019, has attracted much attention and several papers were published recently (Stephan & Muller., 2022, Krzemnicki e
Investigating the Provenance signature of Tourmaline-Bearing Turquoise in the Kuh Zar Gold Deposit, Semnan Province, Iran
The Neyshabur reserve in northeast Iran is renowned for its production of Persian turquoise, yet it is not the sole deposit associated with this valuable gemstone. The Kuh Zar mine
Gemological and Luminescence Characteristics of Taaffeites from Mogok, Myanmar
Taaffeite is a rare gem that has been found in different localities such as Tanzania, Sri Lanka, China, and Mogok, Myanmar. Systematic research on the taaffeite from Mogok, Myanmar
Study and investigation of garnet from Balangir in Odisha, India
n the present study investigation of almandine-pyrope garnet, found in the Khaliapali village (20.8639° N, 83.4708° E) located in Balangir Tehsil of Balangir district of Odisha s
Sulfur-based species induced photochromism in sodalite
Sodalite Na4 (Al3 Si3 O12)Cl is a natural aluminosilicate mineral that contains sulfur or sulfur-related defects, known as chromophores (Reinen et al. 1999; Fleet et al. 2010). Hac
Colour change Paraiba tourmaline from Brazil
In just a few decades Paraiba tourmalines have developed into one of the most valuable and sought-after gems in the world. Of particular interest are specimens from the legendary B