This article reports on the recent mining and production status of ruby in Longido, Tanzania.
Faceted-grade rubies and their matrix from Longido Area, Tanzania, were investigated by …

Mogok gem corundum samples from twelve localities were analyzed for trace element
signatures (LA-ICP-MS method) and oxygen isotope values (δ18O, by laser fluorination) …

The geographic origin of gem corundum has emerged as one of its major value factors.
Combined with gemological observations, trace element analysis is a powerful tool for the …

The study is based on the determination of trace elements in ruby samples, Ti in particular,
using laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS). The …

For decades, unraveling the heat treatment of sapphire has been a challenging issue. The
present study offers new aspects that support the detection of heat treatment of sapphire …

The chemical composition and spectra of untreated and heat-treated rubies from
Mozambique and Madagascar were analyzed by an electron probe microscopy analysis …

In the past several years, Mozambique has emerged as one of the world's most important
sources of ruby, and unheated stones from this country are in particularly strong demand …

Geuda is a variety of corundum gems commonly found in Sri Lanka and Madagascar.
Geuda lack colour and clarity compared to other sapphires yet has the potential to convert …

Over 75% of the gem-bearing gravels in Sri Lanka belong to the corundum species of
gemstones. Geuda is a low-quality form of corundum, and it is abundant in most gem …

Purple coloured natural ruby has been studied by surface sensitive tool like XPS supported
by XRD, X-ray tomography (micro CT), FESEM, TEM and EDS. While XPS and EDS …