Understanding Stibnite
Gem-A assistant gemmology tutor, Dr Juliette Hibou FGA explores the history, origins and chemical composition of the mineral, stibnite, which can be found in the Gem-A Gemstone & Mineral Collection. Stibnite is an antimony trisulphide mineral with the chemical formula Sb2S3. It is a natural mineral source of the chemical element antimony (Sb), which is […]
Explore the History of Garnet in Antique Jewellery
Gems&Jewellery is delighted to welcome jewellery historian and valuer, John Benjamin FGA DGA FIRV as our columnist for 2019. As part of a new Gemstone Conversations series, John explores the history of the use of garnet in antique jewellery and tells us why we should give more credit to this special yet undervalued gemstone. I have […]
What Are the Most Important Gemstone Producing Countries in the World?
Gem-A operations manager Charles Evans FGA DGA considers whether gemmologists can put gem-producing countries into an ‘order of importance’ and offers his thoughts on what would make the perfect gemstone-hunting holiday. What if you are a keen gemmologist who has just come into some money, left to you on the express condition that you take […]
How to Identify Antique Edwardian Jewellery
Understanding how to identify jewellery from different eras and design movements is essential for historians, valuers and antique collectors. Here, Starla Turner FGA GG offers us a glimpse into the refined and elegant world of Edwardian jewellery and describes the motifs that make pieces recognisable. Fashion of the Edwardian Era The short reign of King […]
Breaking down the Misunderstandings about Precious Coral
Inspired by Pantone’s ‘Color of the Year 2019’, Rui Galopim de Carvalho FGA DGA dives into the underwater world of precious coral and addresses some of the misunderstandings around its use in the jewellery industry. The colour of many precious corals has been announced as the ‘Color of the Year 2019’ by Pantone, the US-based […]
Understanding Sugilite
The Gem-A Gemstone & Mineral Collection contains this vivid purple sugilite specimen. Here, assistant gemmology tutor, Dr Juliette Hibou FGA, explains more about this unusual mineral that was only discovered in 1944. The mineral sugilite is a relatively recent discovery. The Japanese petrologist Ken-Ichi Sugi (1901-1948) from the Imperial University in Kyushu was the first […]
Buying Guide: Coloured Diamonds from Least to Most Valuable
The typical image of a diamond tends to be of a clear and colourless stone, therefore it is hardly surprising that these are presumed to have the highest monetary value. In reality, diamonds can present as a range of different colours and uniquely-coloured diamonds can command premium prices. Coloured diamonds are created when impurities or […]
Gem-A Gemstone & Mineral Collection: Understanding Selenite
The Gem-A Gemstone & Mineral Collection contains this fantastic selenite specimen with grass-like green blades that shoot-out from the host rock. Assistant gemmology tutor, Dr Juliette Hibou FGA, explains more about the origins and properties of this striking gem material. Although sometimes used as a synonymous for the mineral gypsum, selenite strictly refers to the colourless […]
What Makes A Gemstone Rare? Diamond, Painite, Grandiderite and More
The term ‘rare’ is thrown around alot online, but what gemstones actually deserve the term and do diamonds fall into this category at all? Gem-A tutor manager, Rona Bierrum FGA DGA, explores some of the rarest gemstones known to man and considers how rarity is measured in the gem and jewellery trade. The term ‘rarity’ […]
What is the Link Between an Emerald and the Emerald-Cut?
Sometimes, we come across terms in gemmology that cause confusion. We all recognise the beautiful green colour of an emerald, but then there is also an emerald-cut diamond that has nothing to do with the green gem itself… or does it? Here, we explain the story behind the terminology. Let’s start with an emerald An […]
