Carobs are a girl’s best friend

Diamond sitting on written page

You know you’ve got problems when you’re flicking through a jewellery catalogue and your eye homes in on the etymology tidbits rather than the diamonds.

The tidbit in question comes from the Hamilton and Inches catalogue:

The word “carat” when applied to gemstones is a unit of weight. It is a distortion of “carob”: the carob bean weighs a reliable one fifth of a gram and could therefore be balanced in the weighing pan against an equivalent weight of gemstones and a deal could be struck.

Here’s the full etymology (from the Online Etymology Dictionary):

mid-15c., from M.Fr. carat “measure of the fineness of gold” (14c.), from It. carato, from Arabic qirat “pod, husk, weight of 4 grains,” from Gk. keration “carob seed,” lit. “little horn” dim. of keras “horn.” Carob beans were a standard for weighing small quantities. As a measure of diamond weight, from 1570s. The Gk. measure was the equivalent of the Roman siliqua, which was one-twentyfourth of a golden solidus of Constantine; hence the word took on a sense of “a proportion of one twentyfourth” and became a measure of gold purity (1550s). Eighteen carat gold is eighteen parts gold, six parts alloy. It is unlikely that the classical carat was ever a measure of weight for gold.

Back to diamonds. Here’s the Online Etymology Dictionary again:

early 14c., from O.Fr. diamant, from M.L. diamantem (nom. diamas), from V.L. *adiamantem (altered by influence of the many Greek words in dia-), from L.adamantem (nom. adamans) “the hardest metal,” later, “diamond” (see adamant). Playing card suit is from 1590s; Sense in baseball is Amer.Eng. 1875.

Hamilton and Inches describe them thus:

Diamond, the hardest substance in nature, is made of carbon. Ideally they are flawless and colourless – or naturally coloured by, say, boron (which turns them blue), or a slip in the atomic lattice (which makes them pink).

“A slip in the atomic lattice” — isn’t that lovely? Atomic lattices refer to the arrangement of atoms into a crystal structure (thank you, Wikipedia). They feature (as graphene, another form of carbon — less glamorous than diamonds, but pretty amazing) in this year’s Nobel Prize in Physics, won by Andre Geim and Konstantin Novoselov (University of Manchester, UK). You can see diamonds’ atomic lattice in the University of Leicester’s Crystal Atomic Lattice Viewer (make sure you rotate the structures — it’s really cool!).

If you can’t afford diamonds this Christmas, you can read about them and do some good at the same time. Hamilton and Inches are taking part in the Stone Paper fund-raising initiative, along with author Alexander McCall Smith and 500 Miles, the charity (founded by Olivia Giles) that supports amputees and other disabled people in Malawi and Zambia. I haven’t seen the Stone Paper book but imagine it will be pretty entertaining. All proceeds from the sale of  the book will go to 500 miles.

The image is by Anne (Afternoon Sunlight) and features the diamond’s “fire”, “which shows up in the rainbows around bright spots, and in the coloured fringes on text”.

By Marian Dougan

Published by Marian Dougan

Marian is a translator and editor (specialising in web content) currently based in Glasgow, Scotland. Marian previously lived in Italy for over 20 years, working as a language teacher, translator and policy analyst with the British Embassy in Rome. A qualified member of the Institute of Translation and Interpreting (ITI) and its Italian-language and ITI Scotnet networks, she is currently Scotnet's Convenor and Deputy Webmaster. From 2003 to 2006 Marian taught translation skills at the Italian Department of Glasgow University and now gives Master Classes as part of the new Masters in Translation Studies course. She also conducts web-writing and usability workshops to help people improve their websites and communicate more effectively with their readers, users and customers. In September 2014 Marian obtained User Experience Certification, with specialisation in Web Design, from the Nielsen Norman Group. She loves language, especially English, and is convinced that learning languages opens up people’s minds and horizons (and increases their brainpower!). To share her enthusiasm, she advises schools and educational authorities on language skills and enterprise. She gives talks to pupils on how to combine language studies with other subjects and so enhance their potential and increase their career options. Marian is an active member of organisations such as: Scottish Council Development and Industry (SCDI); Association of Scottish Businesswomen; Dunbartonshire Chamber of Commerce and the Italian Chamber of Commerce in Scotland. She also loves architecture, design, fashion (British Vogue!), cities and chocolate. She’s a great fan of Twitter and you can also find her on Linkedin.

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    1. My pleasure. I love mining the rich seam of language and unearthing these delightful nuggets scurrying after words and spending way too much time doing things like spinning atomic lattices.

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