This classification of gem corundum (ruby and sapphire) deposits takes into consideration
petrographic data, and the mode of genesis of the deposits. It is aimed at being practical and …

Recent discoveries over the last decade of new gemfields, exploitation of new and existing
deposits, and application of relatively new techniques have greatly increased our …

Using ICP-MS–LA analyses, we demonstrate that the use of the Ga/Mg ratio, in conjunction
with the Fe concentration, is an efficient tool in discriminating between “metamorphic” and …

Gem corundum, a minor but persistent megacryst in east Australian basalt fields, is mined
from some placer concentrations. Laser ablation, inductively coupled plasma mass …

Volcanic rocks in Thailand are widely distributed in both time and space, although most
occur in a broad swathe that extends from Northern to SE Thailand (Figs 15.1 & 15.2). They …

Metamorphic petrology observations on rubies found in-situ in their host-rock are combined
with geochemical measurements and optical microscopy observations on the same rubies …

Determination of gem provenance is a topic of research in the gemological community for
financial, security, and societal reasons. Laser-induced breakdown spectroscopy (LIBS) and …

Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) is an important
technique for quantitative chemical analysis. The authors have applied this minimally …

Corundum xenocrysts from alkaline basalt fields differ in characteristics and hence
lithospheric origins. Trace element, fluid/melt inclusion and oxygen isotope studies on two …

Potential sources for alluvial gem corundum and zircon from the Rio Mayo area, near
Mercaderes, Colombia are reviewed, based on U–Pb dating of syngenetic and protogenetic …