Past conferences
Abstracts Library
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
An implementation of machine learning in ruby and sapphire origin determination
Country-of-origin is one of the most important value factors of corundum (ruby and sapphire) due mainly to its historical or legendary popularity in the trade. Generally, gemmologi
Past, Present and the Future of IGC
Exactly, seventy-one years ago, in the month of October, to be precise from the 23rd to the 25th of October 1952 in Lugano, Switzerland, the inaugural meeting of the International
Effects of weathering on FTIR spectra and origin traceability of archaeological amber: The case of the Han Tomb of Haihun Marquis, China
Amber (fossil resin), known as the “capsule of time and space”, which is a complex biogenic polymer originated from ancient plants resin from different geological periods [1].
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).
FTIR Fingerprinting: a case study on mineral inclusion identification by FTIR applied on rubies from marble-hosted deposits
Fourier-Transform Infrared Spectrometry (FTIR) is a well-established analytical method in the field of gemmology (Suhner, 1979; Fritsch and Stockton, 1987; Smith, 1995; Beran and R
Milky appearance of Geuda sapphire from Sri Lanka
Sri Lanka is famous for gems since several thousand years. Almost corundum varieties have been found in Sri Lanka including the rough of Geuda which has also given considerable att
Analysis of Myanmar golden-lipped cultured pearls using X-ray radiography, EDXRF, UV-Vis-NIR and Raman spectroscopy
Myanmar golden-lipped pearl oysters (Pinctada maxima) are well-known to be found at the Myeik Archipelago – formerly also known as Mergui Archipelago – in the Andaman Sea in so
Fingerprint differences between Emeralds from two main zones of production in Colombia in response to input from their host rock
Although there is information about techniques to separate Colombian emerald material from that of other countries, not much information is available on how to differentiate Colomb
A study of nickel-bearing type Ia diamonds
We present a detailed FTIR and PL spectroscopic study (i.e. at 298 and 77°K) of a large number of colorless (i.e. color D to G) type Ia diamonds (i.e. >200), showing the presence
Mapping underground rivers at the Copeton Diamond Field, New South Wales, Australia. Following these “deep leads” to further riches
In Australia’s ‘New England’, early gold and tin explorers discovered diamonds in their sluice boxes without realising their significance, but by the 1890s the Copeton-Bingar
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
Baltic amber and its inclusions: an insight into the origin and nature of the trapped material
Amber is a fossilised resin from ancient trees (coniferous and deciduous), which underwent the process of fossilisation in various epochs and depositional environments. Until the p
Proposed New Filler Type for Emerald Fracture Filling: Design, Detection, Differentiation, Disclosure
Fracture filling is common in gem trading to enhance gemstones’ beauty and / or durability. Common textbook examples are (lead) glass filling of rubies and diamonds, polymer/resi
A nuummite occurrence from kangerluarsuk in the Maniitsoq Region, West Greenland
K. I. Giesecke was the first to recognize the beauty of the iridescent amphibolitic gemstone Nuummite in 1810 when he collected samples from the island Simiuttat in the Nuuk area,
Purple to bluish grey chalcedony from Ethiopia
In the past 15 years, Ethiopia has repeatedly gained attention for a variety of new gem finds. In 2008, a large deposit of white play-of-colour opal was found (Rondeau et al., 2010
Snapshot of rubies from 1915
In 2008 the Honourable Mary Montagu Scott oversaw the opening of a permanent exhibition at Buckler’s Hard Maritime Museum on the Beaulieu Estate about the steamship SS Persia (Fi
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
Geographic Origin Determination of Fei Cui: A comparison of high-quality green Fei Cui from Myanmar, Guatemala, and Italy
Fei Cui is a kind of jade that is defined as a granular to fibrous polycrystalline aggregate composed solely, or principally of any of the following or any combination of the follo