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Testing of antique jewellery at SSEF may provide insights which go far beyond simple gem testing. They add valuable information to the jewel, starting from its design and craftsmanship in the making, the choice of colours and qualities of gemstones, or the facet arrangement and proportions of old cu

Vanadium as a colouring element is quite often underestimated, mostly as it is often associated and acting together with chromium, a chemical element with a similar geochemical behavior and paragenetic occurrence but which is historically better known in the trade and easier to detect with simple to

Paraiba tourmalines owe their attractive colour to the presence of copper. In the best case, this gives rise to a vivid blue colour, also known in the trade as ‘neon’ blue or ‘electric’ blue and not known from any other gemstone in nature.

On the 8th of June 2023, the Estrela de Fura ruby was sold at Sotheby’s in New York for a world record price of US$ 34.8 million. This ruby of 55.22 ct was cut from a 101 ct piece of rough, discovered in July 2022 near Montepuez in Mozambique, in a mine operated by the Fura Gems company.

Recently, a beautiful Vietnamese ruby of 2.10 ct and vivid red colour was submitted to SSEF for testing. Microscopic observations and chemical trace element analysis confirmed its Vietnamese origin and our colour grading protocol revealed that this stone was well fitting to be called ‘pigeon blood

Having attended the IGC conference in Tokyo in October 2023, Dr. Michael S. Krzemnicki and Dr. Laurent E. Cartier took some time to travel south to visit the cultured pearl trading hub of Kobe and pearl farmers in Mie prefecture.

Since January 2019, SSEF offers the gem trade a tracking service and document, known as SSEF GemTrackTM. It not only allows the client to track a gemstone in time, but is also an attractive option for our clients to tell the story of the provenance of a specific and exceptional gemstone to their cus

Gamma irradiation is a treatment method that may enhance the colour and visual appearance of gemstones, such as diamond, topaz, quartz, and corundum, to name a few. This treatment method uses strong gamma rays, either from radioactive isotopes like cobalt-60 (60Co) or from a linear accelerator (LINA

Sodalite, a complex tectosilicate with the ideal formula Na8Al6Si6O24Cl2 is known in the trade mostly as dark blue ornamental material, often as translucent to nearly opaque beads and cabochons, but in rare cases also as transparent faceted stones.

Since ancient times, the Badakhshan Province in northeastern Afghanistan has been known for its gem deposits, most prominently the lapis lazuli mines near Sar-e Sang in the Kokcha valley.and cabochons, but in rare cases also as transparent faceted stones.

Afghanistan is known since ancient times as source of exceptional gems, namely lapis lazuli, tourmalines, beryls, rubies and spinel (Bowersox & Chamberlin 1995). Apart from these rather classic gemstones, Afghanistan is also source for numerous rare collector minerals, such as väyrynenite, triplit

The Mogok area in northern Myanmar has been known as a major source of rubies and other gems since historic times. Often referred to as the ‘Mogok Stone Tract’, this gem-rich area is located within the central part of the Mogok Metamorphic Belt which forms part of a larger metamorphic belt struc

Any gem hunter will tell you that collecting minerals from the soil is a hard job, especially if done in a remote place with rather dry and hot climate conditions and hard rocky soil. So, why not have small and hard-working animals such as ants do the work for you?