Career as a Gemmologist: Olga González FGA DGA

gemmologist using a 10x loupe to study a gem

  A Gemmologist’s Journey: From Painted Rocks to PR Success Early Fascination and Educational Foundations Olga González FGA DGA, the CEO of Pietra Communications in New York City, discovered her passion for gemstones in an unconventional way. As a child, she collected ordinary rocks from her yard and painted them with nail polish, creating her […]

Gem Knowledge: Understanding Spectroscopy in Gemmology

Diffraction pattern Beryl var. Emerald

Spectroscopy is the observation or measurement of the absorption and emission of electromagnetic radiation by gemstones. Today, this methodology and its associated tools are vital for gemmologists and can be used to reliably indicate a gemstone’s identity. Here, Gem-A Gemmology Tutor Pat Daly explains more about the history and significance of this scientific technique.   Sir Isaac Newton observed the spectrum of […]

Career as a Gemmologist: Liz Bailey 

Liz Bailey auctions

Elizabeth Bailey BA(Hons) MA FGA DGA CPAA works currently at Doerr Dallas Valuations, providing formal valuation reports for probate, insurance, and division of assets, focusing on fine jewellery, watches, and silver. She’s the ex-chairperson for our Gem-A North West branch. Early Passion for Decorative Arts and Antiques  From childhood, Liz developed a deep fascination with […]

Gemmology Insights: What Are the Rarest Colours in Gemstones?

Main image: A group of cut and polished tourmaline gemstones in a range of colours, photographed by Gabriel Kleinberg.

Colour is one of the most appealing features of gemstones and is often the main reason why they are valued. However, it is also true to say that some mineral colours are rarer and more prized than others. Here, Gem-A Gemmology Tutor Pat Daly explores the nuanced world of colour in gemstones, including brilliant reds, Kashmir sapphires, […]

Career as a Gemmologist: Robin Hansen FGA

Robin Hansen

Robin Hansen FGA BSc (Hons), grew up in a science-loving family, who embraced her love for rocks and colour, leading to her education – including Gem-A Diploma – that made her career at the Natural History Museum possible. She’s also a speaker in the upcoming Gem-A Conference ; her talk is titled  ‘Hidden Gems: Secrets of […]

Beginner’s Guide: The 8 Most Popular Diamond Cuts and Faceting Styles

VS1 clarity round cut diamond

When we look at faceted gemstones, we see and appreciate their colours, transparency, brilliance and fire. What we sometimes take for granted, however, is the fashioning that makes it possible to enjoy these visual effects. To explain more, Gem-A Gemmology Tutor Pat Daly has created this useful introduction to diamond cut and shape, incorporating faceting […]

Career as a Gemmologist: Dr Çiğdem Lüle

Dr Cigdem Lule

Dr. Çiğdem Lüle is a mineralogist and a gemmologist who specializes in independent appraisals and litigation support for gems, minerals, and jewellery. One of the pioneers in the field of archaeogemology, she has spent decades researching ancient gemstones and their origins. She’s also a speaker in the upcoming Gem-A Conference ; her talk is titled  […]

Gemmology Insights: How To Recognise Dyed Gemstones and What to Look Out For

Sapphire beads dyed

Dyeing is probably the most common and cheapest way to treat gem materials, to make inferior stones seem to be of good quality or to substitute inexpensive materials for costly natural stones. Here, Gem-A Gemmology Tutor Pat Daly takes a closer look at dyed material and explains how experienced gemmologists can identify evidence of such […]

Gem Knowledge: What is Artificial Glass Paste in Antique Jewellery

Blue purple paste oval faceted

Gemmologists often encounter simulants of natural gemstones, like artificial glass paste. Synthetic and composite stones of various kinds may be troublesome to identify, but those made of glass are among the most common and are usually easy to recognise. As Gem-A Tutor Pat Daly describes in the article below, glasses may also be natural stones, […]

Gemmology Insights: Once in a Lifetime Inclusions for Gemmologists

inclusions in emerald

The fascinating internal world of gemstones is an important area of study for gemmologists. Although some inclusions are common, others are far rarer and more elusive. Some professionals may go their entire lives without seeing these specific internal features in person. Here, Gem-A Tutor Pat Daly shares some ‘once in a lifetime’ inclusions and what […]

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The Gem-A office will be closed from 3pm Wednesday 24th December 2025 for the holidays, reopening 9am Friday 2nd January 2026.

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