Learning about all things Pearls!
This month, our in-store Gemologist, Anna, attended a Gemological Institute of America (GIA) Pearl Grading course after being offered a GIA scholarship. The course was being run by Anu Manchanda, DGA, FGA, GIA GG, a very well known figure in the gemology world. “I attended another course with Anu and found her so enthusiastic and energetic that she inspired me to become a Valuer” said Anna, “so naturally I jumped at the chance of learning more from her”.
In the heart of the historic Birmingham Jewellery Quarter, the course was run in the beautiful building of the Birmingham Assay Office. “Having spent most of my career in London and the South East, it was really nice to venture up to the Midlands and see the Birmingham Jewellery Quarter”.
Already a GIA Graduate Gemologist, Anna wanted to further her education by learning how to use the GIA’s pearl description system. “Having only touched upon pearl grading during my gemology studies, I was keen to learn more about the fascinating world of pearls as they are a timeless classic and popular in both antique and modern jewellery. It is important to grade pearls accurately, not just for my Valuation work but also when sourcing pearls for our stores.”
Covering natural and cultured pearls, saltwater and freshwater pearls, the course comprised all aspects of pearl grading and Anna learnt how to grade using the 7 Value Factor grading system.
“I think the most fascinating characteristic of a pearl is its Colour” said Anna. The colour is made up of three different values:
- dominant bodycolour,
- overtone – the subtle colour that seems to float over the surface of the pearl, and
- orient – the play of colour or iridescence which is evident when the pearl moves.
These black Tahitian pearls vary in overtone from pink to green.
Luster is another important characteristic and is defined as the light that is reflected from the surface or sometimes from within the pearl creating “an inner glow”. Luster can be bright, shiny and glossy while others have a more subtle satin finish.
Shape can vary considerably because pearls are a natural product. Although the more valuable pearls tend to be regular and symmetrical, the more unusual shapes, known as Baroque, have a unique appeal and charm all of their own.
Other factors that need to be graded include size, surface, nacre, blemishes and matching (eg. string of pearls).
“We learnt about the commercially important types of pearl which include Tahitian, South Sea, Akoya and Chinese Freshwater Pearls. Examples of all of these can be seen in-store.”
9 Interesting Facts about Pearls
- Historically, pearls have represented purity and beauty.
- Pearls are the only jewels to be created by a living animal, a mollusc.
- All pearl oysters are born male and transform into females around 3 years old.
- Freshwater pearls make up 95% of the total global pearl production, the majority farmed in China.
- Freshwater mussels may produce 30 to 50 pearls at a time, while a salt water mussel typically grows only one.
- “Mother of Pearl” comes from the oyster shell.
- Rub a pearl against your teeth – real pearls will feel gritty while imitations will be smooth.
- One of the most famous pearls in the world is “La Peregrina” (Spanish for pilgrim). The original weight of this pearl was 223.8 grains (equivalent to 55.95 carats) but after drilling and cleaning, the weight dropped to 203.84 grains.
- People were fishing for pearls over 3,000 years ago – evidence has been uncovered in excavations at an ancient settlement in Bahrain, near Saudi Arabia.
How to Care for Pearls
You need to take care of pearls as they are not as tough as other gemstones and can easily be damaged by contact with hard surfaces. As they are porous, pearls are particularly susceptible to chemicals. Perfume, makeup and hairspray all contain ingredients that can permanently dull a pearl’s appearance. Cleaning products containing chemicals such as ammonia and chlorine can quickly damage pearls and even chlorinated swimming pool water should be avoided.
Pearls require moisture, so you should consider where you store them – avoid airtight containers. The human body provides just the right amount of moisture and so pearls that are regularly worn and properly cared for, will look fantastic for decades. Just clean your pearls with a soft damp cloth, ideally after each time you wear them.