About us

Owner and researcher is MSc (Ir) William Wold FGA. He studied chemistry at the University of Groningen. In 2004, he completed the two-year study in Gemstone Science (gemmology) at the GEM-A in London. The training is an accredited HBO course for gemmologists.

He teaches jewellers, goldsmith and interested parties who want to know more about gemstones and the research methods. He has been president of the gemologists of the Dutch trade union of 2008-2017 as well as the Gemstone Association Gemma as chairman 2008-2018.

Coresearcher is Ariane Sikkema FGA DG. She successfully completed her studies at the GEMA in 2008. In 2011, she made her diamond gradueerders training at the Hooge Council for Diamant (HRD) in Antwerp. In Europe, the training of the HRD is the most prestigious training in the fiels of diamond grading.  She also specialises in garnets and teaches jewellers and goldsmith. From 2010 to 2017 she was the secretary of the Dutch Gemologists trade union.

Building knowledge on gemstones on an international level

 In the trade of gemstones people are constantly looking for new treatments or new syntheses to upgrade gems. Through international contacts,  visits of congresses in Europe and Asia and memberships of various gemmological associations we keep abreast of the latest developments. The laboratory is a member of 

  • Dutch Association for Gemologists (VVNE)
  • Acredited Gemologists of America (AGA) 
  • Gemmological Institute of America GIA the GEMA (Gemmologcial Association of Brittain)
  • Deutsche gemmological Association (DGemG) 

To keep abreast of developments in gemmological science, we also conduct research on new gems and new treatments or new identification methods. In 2008, a study on colour changing stones and the prediction of the extent of the effect based on spectroscopic studies was awarded a third prize at the European Gemmological Congress in Bern. The laboratory possesses a very large collection of reference material of both natural gemstones, treated natural gemstones, as well as synthesises and the many imitations that is now available on the market.

Methods and instrumentation

We work according to the laboratory code drawn up by the CIBJO. The terms used for gemstone identification correspond as described in the Blue books of the CIBJO.
For diamond terminology the ISO NENenISO 18323-2015 is used. The laboratory‘s working method is accordance with the international standard for laboratories ISOIEC DIS 17025-2017. 
Laboratory instrumentation consists of: 
  • Microscope
  • Refractometers 
  • diamond standards and lighting for grading
  • density determination scale
  • polariscope
  • reflection measurement
  • thermal conductivity measurement
  • XRay
  • Spectophotometer
  • Raman
  • IFTR
With this instrumentation it is possible to identify all gems and most of the treatments.