Periodycal #12: Coronation chemistry & coke in cola

Celebrating stolen gemstones and the days of hard drugs in soda

Andy Brunning

May 5, 2023

Welcome to another edition of the Periodycal newsletter! Ahead of the coronation of King Charles III, this issue features a look at the chemistry behind the gemstones in the coronation crowns. There’s also a new graphic on some unexpected compounds historically found in sodas, as well as the usual round-ups of upcoming significant dates with chemistry links and interesting chemistry news and features.

Coronation crown chemistry

Infographic on the chemistry of the coronation crowns: St Edward's Crown, the Imperial State Crown, and Queen Mary's Crown. The graphic shows the various gemstones in each crown and provides a brief description. — Click to view and download the full graphic on the Ci sitee

This weekend the UK is gearing up for the coronation — a somewhat stuffy celebration of an elderly man finally having an exceptionally heavy lump of jewel-encrusted metal balanced on his head for a relatively short period of time. Think of it as an oddly tame endurance test for the excessively privileged.

I’m very much in the ‘largely indifferent’ camp when it comes to the coronation, in case the above paragraph didn’t drop a heavy enough hint. However, I’m also never one to pass up the opportunity to tenuously link anything to chemistry, so this week’s latest graphic looks at the compositions of the various gemstones that adorn the three crowns used during the coronation ceremony.

The graphic also very lightly touches on the controversy that surrounds the Koh-i-Noor diamond which was previously mounted in Queen Mary’s Crown, but which won’t be being restored to the crown to try and avoid reigniting the controversy over its ownership. Unfortunately for the Royals, the controversy of the ownership of the Cullinan diamonds which will be being used in its place has just been stirred up instead.

Clinging onto artefacts seized in the name of empire which don’t actually belong to us is arguably part of the British identity at this point, so I’ve no doubt little will come of the latest arguments over gemstone ownership. I feel like I could watch a coronation commentary which just highlighted what was stolen from where in the various props used throughout the ceremony, perhaps with a bit of their chemistry thrown in. But hey, not going to happen!

Coke in Cola

An infographic examining the chemical history of soda. The first half of the graphic highlights the different methods historically used to carbonate water. It starts with the production of carbon dioxide via the reaction of chalk and sulfuric acid. Today, a pressurized injection method is used. The second half of the graphic looks at interesting compounds historically found in some sodas, including cocaine in Coca-Cola and lithium citrate in 7Up. — Click to view and download the full graphic on the C&EN site

We’ve all heard the story that Coca-Cola used to contain cocaine. The latest edition of Periodic Graphics in C&EN looks into that and other unexpected historic ingredients in sodas. There’s also a short history of carbonation and the different methods historically used.

Upcoming chemistry tie-ins

Here’s a quick run-down of upcoming events or days and links to some relevant chemistry graphics from the archives:

9 May: Anniversary of first contraceptive pill approval — The chemistry of oral contraceptives
10 May: National Lipid Day — A guide to the different types of fat
12 May: Dorothy Hodgkin’s birthday — Dorothy Hodgkin and X-ray crystallography
16 May: National Barbecue Day — The chemistry of barbecue

Chemistry news and features

Here’s the regular selection of chemistry news and features I’ve found interesting over the past couple of weeks:

Overlooked documents shed new light on double helix discovery — This is an interesting look into the detail of the discovery of DNA and the contributions of Rosalind Franklin. The Twitter thread summarising the findings is also worth a read.
The highly corrosive world of superacids — A short and accessible summary of superacids, useful for answering the ‘what’s the strongest acid?’ question!
Swarming locusts can deploy a chemical to avoid being cannibalized — Young locusts release phenylacetonitrile to stop other locusts eating them.

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That’s all for another fortnight! If you’re enjoying the newsletter, please do share it with others who might enjoy it too. Any suggestions for new posts or topics for the newsletter are always welcome!

Thanks for reading,

Andy