A Question of Coating Diamonds to Reduce Dirt

Given that diamonds can easily catch oils and become dirty if we coat the surface with fluorine atoms can we make diamonds oil resistant and no longer require cleaning like Teflon coated pans?

This question was asked on the question and answer website Quora. It was the first question that I attempted to answer on that site. This is what I wrote:

While I think it might be technically possible to coat a diamond in teflon, there are some issues which you would need to consider:

Jewellers and jewellery buyers are very suspicious of treatments, including coatings. While teflon is colourless, a dye could be added to enhance the colour of the diamond and make it look better than it actually is. Gemstone buyers are willing to pay a premium for natural, untreated stones.

One of the things that makes a diamond beautiful is its exceptional hardness, which allows it to take a very high polish. A coating would not be able to take such a high polish and would be less attractive.

Teflon is softer than diamond, so it would easily rub off or get scratched away from the diamond surface. Again, this would make the surface appear less highly polished and therefore less attractive.

The refractive index of teflon is very different to that of diamond, it is much lower. But it is somewhat higher than air. This means light entering and leaving the diamond will refract differently to how it does if it enters the diamond directly. This means the diamond would need to be cut with the facets at different angles to the way they currently are, which is to maximise the amount of light reflected from the stone and the play of colour. This would not be a difficult thing to do, but it commits the stone to being a teflon coated stone. If the owner changed their mind and decided to remove the teflon, the stone would need to be recut to maximise its brilliance.

Since I answered this question on 22 December 2018, it has attracted 46 views and no upvotes. That is a bit disappointing as I think I did a good job. But the question is quite obscure, I can’t imagine too many people having sleepless nights wondering if they could put teflon on a diamond’s surface.

I think I chose to answer that question for my first attempt because it would not attract too much attention and I could expect to have it all to myself. So, just a first toe in the water.

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Three Historians Talk about Pearl History

https://www.bbc.co.uk/sounds/play/w3csyp4p

A recent BBC radio discussion about the history of pearls, featuring Victoria Finlay, Beatriz Chadour-Sampson and professor Molly Warsh. It’s a wide-ranging discussion, touching on pearls from a range of times and places. All in 44 minutes, but it’s amazing how much can be covered in such a short time. They also experiment with dropping a pearl into vinegar, testing the legend of Cleopatra and Marc Antony.

I was particularly interested in the discussion of pearls in the Caribbean and the hardships faced by the divers there and in other parts of the world. The change from natural pearls to cultured is also discussed. In many ways, Mikimoto did the world a great service in eliminating the pearl diving business.

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Attempt to Revive Pearl Cultivation in Hong Kong

A video from South China Morning Post shows an effort to revive the pearl fisheries around Hong Kong.

 

The clip shows a seed being planted in the oyster, not a microchip. Perhaps that is inserted after the seed?

In this region, it seems the oysters are destroyed to recover the pearls. I wonder if attempts have been made to use processes which allow the oyster to be used multiple times? If the oysters can survive longer it would reduce the problem of destocking. But perhaps the economics work differently with freshwater pearls.

The video raises more questions than it answers, but a lot of information is conveyed in a short amount of time.

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The Professor Views some Huge Diamonds

The Professor from Periodic Videos is at it again. Alrosa let him handle some huge diamonds, including a few lovely coloured ones and he explores fluorescence again. He discusses types of cut briefly. We also get to see the cutting room, a close look at how a lapidary works at his bench and how lasers are used to quickly cut off large sections of unwanted gemstone material.

 

I was surprised to see that the laser leaves a black surface on the stone on the face it cut. But I should have expected it as a laser works by burning material. The diamond material, where the laser cuts, is converted into graphite by the heat. It really does generate a lot of heat, so water has to be directed onto the cutting surface to cool the stone, otherwise the diamond itself could ignite. That water, of course, then needs to be cleaned of graphite and re-cooled so it can be recycled. I don’t know why they don’t just dispose of the used water and use fresh, cold water for diamond cutting. Maybe it’s special water?

A huge pink diamond is showcased throughout this video. It seems Alrosa is expecting to sell it for some $tens of millions. It certainly is beautiful. There is also a big purplish pink diamond and a bright yellow diamond, which are also valued by Alrosa around the $10 million range.

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Answering Questions on Quora

Just before last Christmas, I started using the social website, quora.com. It’s a ‘question and answer’ site where anyone can post a question and anyone can take a shot at answering. It’s a bit of fun, but sometimes you come across some interesting content. I don’t know if any celebrities use that site, but some seem quite well qualified (according to the credentials they give themselves). Some answers are quite well referenced anyway, and I’ve learnt a few things from reading them.

Success on that site is firstly measured by ‘views’ (how many people actually look at your answer), then by ‘upvotes’ (how many people hit the button to say they liked what they read), then by ‘shares’ and I guess one’s real status is shown by how many followers you have.

I started trying to answer questions about diamonds, gemstones, history etc. I was getting up to about 50 views on some of my answers, which I think is quite satisfactory.

But after about a month, I happened to answer a question about Indonesia in a slightly controversial way. Well, that answer proved to be very popular. Since early February that answer has had 22,000 views, 426 upvotes and 6 shares. That’s a lot, by my standards. I’ve also acquired a few followers, though I don’t know why they chose to follow me.

A couple of other similar types of answers also proved to be quite popular. You tend to get most of your views soon after you post your answer. The view count might increase over the next few days and then they start to tail off quickly. So an answer that started getting thousands of views per day, after a month is now receiving a few hundred.

Sometimes Quora notices an answer that is getting good results and ‘promotes’ it by including it in the Quora Digest, an email it sends out to Quorans every day or every week, depending on what they’ve subscribed to. Some of my answers have made it to there, and it’s boosted the number of views they received.

But after the success I had with (slightly) controversial answers, I’ve decided to go back to answering questions on diamonds, gemstones and history (for the most part). It’s fun to engage with lots of people, but I prefer the satisfaction of sharing the little knowledge that I have with people to bring them to a better understanding of the topics I’m most interested in.

I also think it might be a way for people to find my book. If they like what I write on Quora, they might be interested to view my profile and find the link to this website and either engage in conversation here or find some of my bigger works.

So far, I think some people have visited here from Quora, but not in huge numbers. Perhaps it will happen as it did when I posted that slightly controversial answer, people will suddenly start visiting here en masse from Quora. But if that doesn’t happen, that’s ok too.

One of the real benefits of using Quora, for me, is to practice my writing and be open to criticism from viewers.

Another benefit is that I can find the questions people are asking about the subjects this blog covers, particularly diamonds for now. I have decided to post here some of these questions and my answers, and sometimes also the answers given by other people. That way, people visiting this site, and not interested in Quora, can engage in the conversation too. I’ll start tomorrow if I’m able to.

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The Professor Washes his Hands in Diamonds

Periodic Videos featured The Professor on a visit to an Alrosa diamond sorting facility. He shows us some amazing diamonds, including some coloured ones. Purple, pink, yellow, octahedrons, cubes, twins. Fluorescent colours.  We also see a few unique shapes such as one that looks like a hollowed-out skull and another rounded crystal with soccer-ball markings.

 

 

Towards the end, he gets to play with a huge basin filled with diamonds. It’s an experience few people get the opportunity to do.

Some of his quotes: “I just can’t believe that nature can make anything quite so beautiful.”

“This is the most extraordinary thing I’ve done on Periodic Videos… and certainly the most fun!”

Considering the amazing things that Periodic Videos have shown in the past, that last comment is a huge statement.

 

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Endpapers for a Soft Cover Book

The Guardian recently acknowledged the obsession of some readers for endpapers. These are the colourful patterned pages between the cover and the rest of the book, usually on hardbacks.

Although there will not be a hardcover edition of Known Only to Kings, Sam has made endpapers for it, and they will be included in the book. As you might expect, it’s a diamond motif, a repeating diamond pattern in light blue. I think it will look elegant.

It’s a little flourish to make the book feel a little bit more special when the reader opens it. Much nicer, to my mind, than a bare white opening.

I’m not sure how much it’s going to cost me. Maybe it was a needless expense. I’ll be interested whether any readers notice it or comment on it.

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How Diamonds are Formed

In Known Only to Kings, I give a brief description of what we currently believe about how diamonds form. As I said, there is a lot we still don’t know about it, and if we did know more, it would probably be easier to find more deposits. Kimberlite and lamproite pipes aren’t the easiest things in the world to find, knowing more about their formation process would surely help us find more of them.

Here is an article published by the Gemological Institute of America, which gives a lot of additional information. It’s not too technical if you persevere with it. There is also a more recent 32 minute talk, which becomes technical quite quickly, but if you read the article first, it might help your understanding.

 

I find with technical stuff it’s best to let it wash over and catch as much as you can. Eventually, you get to understand the words they’re using. It’s a bit like learning a new language.

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The Jewelled Gun of Sultan Mahmud I

Ottoman Sultan Mahmud I came to power mostly by good luck. His predecessor was deposed in a Janissary revolt and Mahmud became a figurehead until the leaders of the revolt became unpopular and a year later they, and 7,000 of their followers were executed. That left Mahmud to reign as he wanted.

And he wanted to write poetry. Affairs of state were handled by his chief ministers. They were involved in a European war, but their best work was done while the Persian emperor, Nader Shah, was distracted in Mughal India. He looted the Koh-i-nur, many other famous diamonds and a vast fortune from India. But it’s not easy to fight on two fronts. In fact, the destruction he brought to India caused the Mughals to ally with the Ottomans for a long time afterwards.

But Mahmud never went on campaign himself, which makes this gun even more symbolic than it already is. We’re so lucky these days to be able to view such a precious object. Notice how the curator handles the moving parts.

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An Idea to Coat Diamonds with Teflon

I attempted to answer a Quora question about the possibility of coating diamonds with teflon so they would not need to be cleaned so often. I pointed out some possible problems with the idea. But it was certainly creative. It will be interesting to see what other people say about it.

In hindsight, I might not have answered the actual question. I will need to try harder on this.

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