Cultured South Sea pearls with small beads
Identifying beaded cultured pearls is usually quite straightforward, as such pearls often contain a large bead made from a freshwater shell with a nacre layer only 1.5 mm or less thick.
Fake it ‘til you break it: Oddities and fraud cases submitted to SSEF
Apart from beautiful and exceptional gemstones, the SSEF also gets from time-to-time submissions which clearly fall far from that prestigious range.
Age dating of burmese jadeite
Recently, the SSEF received a strand of Burmese jadeite jade beads for testing. The beads were slightly graduated with a diameter ranging from 8 to 11 mm and exhibited a beautifully saturated and homogeneous green colour.
Purple substance in hollow tubes to mimic unheated Paraiba tourmaline
Recently, the SSEF received a 14-carat, light blue, copper-bearing tourmaline for testing. Based on trace element concentrations, its Mozambique origin was readily established.
Phosphorescence spectrometry of diamonds
The JASCO FP-8550 spectrofluorometer. The instrument has a variety of applications. Here, we report on the phosphorescence lifetime study of a 0.705 ct, round, brilliant-cut, colourless (H/VS1), natural diamond (reference NBMJ).
Study on sapphires with “exotic” elements and implications for heat treatment detection
In a recent study, we analysed a series of unheated gem-quality sapphires containing ‘exotic’ elements such as Sn, Nb, Zr, Ta, W, also known as high-field-strength elements.
Age dating quality control
Knowing the age of a gemstone can be valuable when determining its origins. Unfortunately, most gemstones cannot be dated directly. However, it is possible to determine the age of certain inclusions commonly found in gemstones.
Renaissance point cut diamond and gold ring
Since the beginning of human history, jewellery has been created, with its materials, including gemstones and precious metals, being reused to make new pieces.
Brazil fieldwork in 2024
Brazil is a historically famed source of gemstones, being a well known producer of various gem varieties - e.g., diamond, tourmaline, beryl and topaz.
Rare encounter: Sapphire with grandidierite needle inclusion
Recently, the SSEF received for testing a sapphire of pale blue colour with a distinct colourless needle-like inclusion, resembling to some extent long prismatic pargasite needles known in Kashmir sapphires.