We dig dig dig dig dig dig dig in our mine the whole day through, To dig dig dig dig dig dig dig is what we really like to do, It ain't no trick to get rich quick, If you dig dig dig with a shovel or a pick, In a mine! In a mine! In a mine! In a mine! Where a million diamonds shine!

The Seven Dwarves singing happily as they excavate some amazing diamonds and other gemstones just sticking out of the surface.

 A Disney View of diamond mining!

So why not buy laboratory grown diamonds? They are cheaper, better clarity and unless being examined by an expert, indistinguishable from natural diamonds. I suppose it's down to personal taste, why you want a diamond in the first instance. Personally I like the fact that natural diamonds are billions of years old created by an act of nature,  I find that amazing, even though I know diamonds aren't the rare commodity the industry would have us believe.
Then there is the argument  that by buying lab grown diamonds you are not adding to the damage to the earth and the exploitation of workers caused by the mining natural diamonds. The diamond industry gives employment to many people, how would a reduced diamond mining industry effect the workers? What alternative jobs are available?
Should the mining industry nationalised, so that the countries themselves benefit? I think I would be more comfortable if I knew the workers were benefitting more from the profits. If the diamond mine owners provided the mining communities with housing, schools, medical support, a decent standard of living and a voice that is listened to without being shot at, arrested and tortured.
I found it really hard to find an image of the inside of a diamond mine to show the working conditions, all I found was this old article (2002),
I really hope conditions have improved since then however the miners strikes in 2012 lead me to believe little has changed. I hope someone can prove me wrong. Here is an article explaining about the strikes.

Not that I want to ruin the pleasure that Diamonds give so many, just highlight the human cost. This is a very complex subject economically, politically and morally, one that I can only begin to comprehend. But what is obvious are that changes are clearly necessary and sooner rather than later.

Listen to Ladysmith Black Mambazo -Nansi Imali (Here Is The Money) ,

Here is the money dug by the men in the mines

Where the fainthearted will not go

We congratulate our men for their bravery

And for risking their lives

We salute you

(written by J. Shabalala) 

Sorry to keep going on! just a quick mention on the subject of Blood Diamonds - since 2003 The Kimberley Process has worked to stem the flow of diamonds being sold to raise monies to fund conflicts. All diamonds sold should have a disclaimer to declare that to the sellers knowledge the diamonds were obtained from sources not associated with the funding wars. How successful have they been?  This article was recently published in the online guardian.

Next blog....

So what other precious gemstones can be grown in a laboratory  - lots!. The first gemstone to be created in laboratory was Quartz all the way back in 1845 this came about not for adornment but for use in industry when in Paris Pierre and Jacque Currie discovered that Quartz was a good conductor of electricity

Much suspected by me, Nothing proved can be, Quoth Elizabeth prisoner.

another use for diamonds, this poem was written with a diamond on her window by 
Queen Elizabeth 1 whilst she was imprisoned in the gatehouse of Woodstock Manor, Woodstock, Oxfordshire.
Did you know that since the 1950's it has been possible to create diamonds in a laboratory. Once scientists discovered that diamonds were formed from pure carbon they set about trying to create diamonds from cheap carbon.
Diamonds are simply crystallized pure carbon, just as rock candy is crystallized sugar—an ordered array of atoms or molecules.
Laboratory diamonds are mostly used in industry for grinding, cutting, drilling, polishing tools and optics. Gem-quality diamonds have only been achievable for a few years and now you can have your loved one or pet turned into a memorial diamond! We are 18% carbon, I guess the bigger you are the larger the diamond.
Laboratory diamonds are made using either  CVD, Chemical Vapour Deposition or HPHT, high-pressure high-temperature diamonds. These diamonds are termed synthetic diamonds,

a quick explanation of the difference between of Synthetic and Simulation.

Synthetic - A material  that is created in a laboratory through chemical-physical processes. A synthetic diamond is a true diamond - pure carbon, crystallised in isotropic 3D form - created by a human controlled process.

Simulation - A material that imitates another one but it is not the same substance. Diamond simulations may be natural (e.g. white zircon, quartz) or synthetic  (e.g. cubic zirconium, glass) and are fairly easy to distinguish from natural or synthetic diamonds.

The HPHT method replicates the process of natural diamond creation.
Three methods of HPHT diamond synthesis are BELT, BARS, CUBIC PRESS - they all use the same principal.
A diamond seed is placed into a reaction cell along with a carbon source such as graphite. A metal solvent or “flux” either Iron or Nickel or a combination of both is used. Using a flux means lower temperatures and pressures can be used to to convert the graphite into diamond.The exact composition of the flux strongly influences the properties of the synthetic diamond. For example, aluminium will remove nitrogen atoms from the synthetic diamond. This results in the growth of a colourless diamond. Adding boron to the growth capsule will result in a blue diamond.
The cell is subjected to extremely high temperatures and pressures – to simulate the conditions of diamond formation in the earths core. This results in the graphite crystallising as diamond. A slow, well-controlled growth is essential for growing high quality diamonds. Only a few minutes are needed to convert graphite into powder sized diamond, but it takes about three days to crystallize a 1ct, rough gem-quality stone.

HPHT created diamonds

CVD is a generic term for a group of chemical processes that involve depositing a solid material from a gas or mixture of gases onto a substrate (base layer).
In the CVD process, to start the formation of a diamond nuclei or nucleation from which the diamond crystal grows, small seed diamonds are used as a substrate. The process generally takes place at below atmospheric pressure. The starting materials for diamond synthesis are hydrogen and a hydrocarbon e.g. methane. The substrate sits within a reaction chamber at a  controlled temperature between 700°C and 1,200°C, the hydrogen-hydrocarbon gas mixture flows in,  microwaves cause the gas mixture to form a plasma which builds up over the seed diamond in ripples creating a diamond.

CVD created diamonds

A  time line to summarise the development of laboratory grown diamonds.

Next time I will look at other lab grown precious stones and discuss the issues of using lab gems.

An Emerald Is As Green As Grass

An emerald is as green as grass;
A ruby red as blood;
A sapphire shines as blue as heaven;
A flint lies in the mud.
A diamond is a brilliant stone,
To catch the world's desire;
An opal holds a fiery spark;
But a flint holds fire. 

Christina Georgina Rossetti

Just wandering away from time pieces for a while. Have you ever been to the Natural History Museum, Exhibition Road, South Kensington? Go to the Vault to see "some of nature's most rare, unique and valuable treasures"Like the Medusa Emerald - on loan there till July 2013.

The Medusa Emerald which was hidden for thousands of years
inside a huge boulder of quartz rock.

A team of experts used state-of-the-art techniques to uncover the emerald discovered in a large boulder of quartz in a mine in Zambia. Several months of delicate work, painstakingly removing the quartz, finally revealed the beautiful emerald crystals. Emeralds are my favourite precious gemstone, more so than diamonds. So why and how do crystal form and what makes some more expensive than others?
First some basic chemistry, Crystals are build out of atoms (an atom is the basic unit of an element, it is a form of matter which may not be further broken down using any chemical means). When two or more atoms combine a molecule is formed. Molecules combine to make elements and when these elements combine Minerals are produced, mostly compounds (more than one element) though some Minerals are made from one element only e.g. Native copper. There are over 4,000 minerals each with a fixed chemical composition. A mineral is defined as being -
1. Naturally occurring.
2. Inorganic.
3. Solid.
4. Having a definite chemical composition.
5. Having an ordered internal structure.
Minerals can have a Crystalline Form - this occurs when a mineral’s atoms or molecules join in a systematic repeating pattern defined by its chemistry and structural arrangement of its atoms. The crystalline form of a mineral determines its cleavage (the way the crystal breaks) and many other properties. Depending on the type, crystalline forms are grouped into 32 geometric classes of symmetry—crystals that are symmetrical with relation to planes, axes, and centres of symmetry. From there, crystals are further subdivided into 7 Crystal Systems on the basis of the relationship of their axes (imaginary straight lines passing through a crystal’s centre). These are 1.Cubic - e.g. diamonds, garnets. 2. Hexagonal - e.g. ruby, sapphire, emeralds. 3. Orthorhombic - e.g. topaz, peridot, tanzanite. 4. Tetragonal -  e.g. zircon. 5. Monoclinic - e.g.kunzite 6. Triclinic - e.g. feldspar, turquoise 7. Trigonal - e.g. quartz.
Crystal Habit - refers to the general shapes of crystals governed by the development of their faces. It depends not only on atomic structure and crystal symmetry, but also on on the environment in which the crystals grew. Mineral crystals may exhibit different crystal habits with differing environments. Conditions for unimpeded crystal growth of beautiful, well-formed mineral crystals are rare. Quartz for example - provided the growth is undisturbed - always grows as 6 sided columns.
Crystals can be described by how well it is formed, ranging from euhedral (perfect to near-perfect), to subhedral (moderately formed), and anhedral (poorly formed to no discernable habit seen). Gold is a soft mineral and is commonly found as anhedral
crystal masses, specimens with euhedral crystals are less common.

Rock Candy - fun to grow but very bad for your teeth!

The best way to understand how crystals grow is to make some Rock Candy, click the link for an easy method.

There are  5 requirements for Crystallisation. 

1. Ingredients - in this case sugar dissolved into heated water so the water becomes super saturated. 

2. Temperature - as the suspension cool cools the amount of solid ingredients it can hold in suspension drops and sugar crystals form.

3. Pressure - pressure has no affect on rock candy, but it takes the proper combination of pressure and temperature for more complex minerals to crystallize.

4. Time - it takes the right combination of ingredients, heat and pressure and these must last long enough for the minerals to crystallise.

5. Space -  The crystals must have room to grow.

The Naica Mine of Chihuahua, Mexico, is a working mine that is known for its extraordinary crystals. Naica is a lead, zinc and silver mine in which large voids have been found, containing crystals of selenite (gypsum) as large as 4 feet in diameter and 50 feet long.

Inside the earth, the ingredients are more complex than this sugar solution. You can have different minerals crystallising from the same solution at different temperatures. Corundum might crystallise first then as the solution continues to cool, topaz might form and later quartz.

Emerald is composed of the mineral beryllium aluminum silicate - Be3Al2SiO6 with traces of the minerals chromium and sometimes also vanadium which give it Emerald its green colour. Click here to read here in detail about the formation of Emeralds. The natural Emeralds that are being mined today are actually relics of geologic events that took place hundreds of millions of years ago, deep in the Earth’s crust. 

The most common crystal is ice, if water freezes naturally it is classed as a mineral and ice is the crystalline form of solid water.

An Ice Crystal

Next time, values, rarity, other uses of gems, laboratory grown gems and more....

Time is what prevents everything from happening at once. ~John Archibald Wheeler

Continuing developments to the mechanisms that drove clocks did eventually lead to increasing accuracy in time keeping.
The invention of the mainspring lead to the development portable timepieces. The inventor of the mainspring is unknown but references to 'clocks without weights' and two surviving examples show that spring powered clocks appeared in the 15th century Europe. The mainspring is a flat ribbon of steel wound in a coil and attached to the gears of a clock. When the mainspring is wound up and released, it drives the gears as it unwinds.
These clocks and watches gained or lost time in such unpredictable amounts that no one thought of using them to tell the time they were seen more as ornaments. These portable clocks were the first timepieces that the more wealthy people could own they weren't worn on the body.

The First Spring Driven Clocks only had an hour hand. The face was not covered with glass. 
The movement was made of iron or steel and held together with tapered pins and wedges,
 screws weren't used till after 1550.

Some sources credit Peter Henlein (1480-1542), a German locksmith  and watchmaker working in Nuremberg as the inventor of the watch as he was a well known craftsman of early "clock-watches" (taschenuhr), ornamental timepieces worn as pendants which were the first timepieces to be worn on the body.
Improvements to the design of the escapement and the methods used to drive these portable timepieces were continually being made.
Want to buy a replica click here

When Christiaan Huygens made the first attempt at a marine chronometer in 1673 in France, he used a balance wheel and a spiral spring for regulation. A balance spring, or hairspring, is attached to the balance wheel, it controls the speed at which the wheels of the timepiece turn and so the rate of movement of the hands. Huygens spring was an improvement on the straight spring invented by Robert Hooke, unfortunately his clock remained inaccurate at sea.

Drawing of one of his first balance springs, attached to a balance wheel, by Christiaan Huygens.
Published in his letter in the Journal des Sçavants of 25 February 1675.

John Harrison eventually created his accurate marine chronometer H4 based on the design of a large pocket watch (his design was too complicated to be replicated on mass).
Pocket watches continued to evolve, the box-like shaped was replaced by more rounded and slimmer cases.
Thomas Mudge's lever escapement (1754) was a great leap forward and is still used in mechanical watches, in a modified form, today.  

Queen Charlotte's Lever Watch and Pedestal
Probably acquired by George III for Queen Charlotte in 1770
(Backplate signed Tho Mudge / London)

Queen Charlotte's Lever Watch and Pedestal made in 1770, currently part of the Royal Collection, appears to have been the first timepiece to use this important development, the earliest known example of the lever escapement. Also, this was the first pocket watch to have an automatic device for compensating changes in temperature.
Still at this time watches were still being produced in small batches in small workshops and owned by the wealthy.
In the 18th century jewels were used as bearings, diamonds became part of some pocket watches and oil was used to lubricate and smooth the movement of the watch parts.
The 1850's saw the introduction of machine made watches, made in Switzerland and the United States, these were eventually produced at such low prices that by the end of the century ordinary people could afford a watch.
Read this interesting story about President Lincolns Pocket Watch
The beginning of the twentieth century saw the introduction of the wrist watch, still seen as a piece of jewellery just for women, but following its successful use in service during the First World War (1914-18), increasingly among men.
More about the development of wrist watches in a future blog.

"knowing the sky, knowing your relationship with the sky, is the centre of the real answer to knowing what time it is." Tom Wujek

I did say I would write more about the development of clocks and watches. Researching this subject has been very interesting and there is so much information that I have condensed into an outline here.
The ancient Greek, Roman, Chinese and Islamic cultures all developed similar methods to mark the passage of time, oil lamps, candles, sundials, water clocks, merkhet, astrolabe. What was clear that these ancient civilisations had some amazing geniuses (or genii for the correct Latin spelling) that were able to use their knowledge of mathematics and astronomy to develop some wonderful instruments; to tell time, to be used as calendars and to track the movements of the sun, moon and stars, for use in astronomy and astrology. Sadly through the passage of time - and wars - these inventions were lost and we had to start again in the West.
Some (not all) of the greats in Time Keeping (click the name to read more) include:
Ctesibius (born in Alexandria around 300 BC) whose improvements to the water clock resulted in a time-recording device whose accuracy could not be improved on for over 1,500 years.
Hipparchus of Nicaea (born in 190 BC) who accurately recorded  the movement of the sun, moon and stars and other planets and developed trigonometry and constructed trigonometric tables and solved several problems of spherical trigonometry
Andronicus of Cyrrhus (born 100 years BC) whose Horologium (time keeping piece) called the Tower of The Winds still stands today. This public clepsydra (water clock) was driven by a stream flowing down from the Acropolis.

The Tower of the Winds, Athens.

Hypatia (born in Alexandria 370 AD) credited with creating a geared astrolabe and a planesphere.
Since ancient times as a kind of analogue computer know as an astrolabe has been used to find the time during the day or night, find the time of a celestial event such as sunrise or sunset and as a handy reference for teaching astronomy. The celestial sphere, containing  the astronomical objects - moon, sun and stars, is projected on to the plane of the astrolabe (stereographic projection). The moveable componants are lined up to correspond to the users current position and once set, the entire sky, both visible and invisible, is represented on the face of the instrument.

Watch this short animation to see a demonstration.
Download an astrolabe app for your iphone here

The Clock at Hogwarts based on the design of an Astrolabe.

There is no one person responsible for the invention of mechanical clocks rather there were developments and improvements.
Original clocks were astrological clocks based on the design of the astrolabes. The Prague Astronomical Clock or Prague Orloj is a medieval astronomical clock. It was installed in 1410, making it the third-oldest astronomical clock in the world and the oldest one still working.

Prague Orloj

So how did we get from those astrological clocks and water clocks to perpetual movement mechanical clocks, it was the development of a mechanism called an escapement.
1280-1320 saw increasing references to clocks and horologes and existing water clocks being adapted to use falling weights to power them. The release of this power was controlled by the escapement. The earliest record of an escapement being used is in medieval China - Su Song incorporated a kind of escapement in his astronomical Clock Tower of Kai Feng (1088) but it was reliant on water to power it. The date of when an escapement was first used in a clock is unknown.The first clear drawing of an escapement was by Jacopo di Dondi and his son in 1364. It is estimated that escapements were being used in mechanical clocks  in the late 1200's. 

Verge and foliot escapement from De Vick clock, built Paris, 1379, by Henri de Vick

The first mechanical clocks were no more accurate than the best water-clock accuracy. However, overtime the improvements to the design of the escapement, the method of driving the mechanism and the materials used to make them lead to very accurate time pieces. Read in detail more here.
Click here to see the British Museums wonderful animated demonstration on how an escapement works.
Salisbury Cathedral has the worlds oldest mechanical clock, installed 1386, that still strikes the hours.
Next blog how watches developed for portable clocks.
If you are really interested in the subject and curious to see old clocks and watches click here to take a look at the Antiquarian Horological Society Website.

I must go down to the seas again, to the lonely sea and the sky, And all I ask is a tall ship and a star to steer her by,

Click here to read the whole poem, one of my favourites - Sea Fever - John Masefield (1878-1967) (English Poet Laureate, 1930-1967).  Carrying on from my last blog dealing with our need to know the time, what is the connection between tall ships, stars and accurate time keeping?  I found this out when when I visited the National Maritime Museum Greenwich.
Increasing voyages of exploration and commerce meant that precise navigation became essential. The method used by Christopher Columbus  - Dead Reckoning- just wasn't good enough nor was Celestial Navigation and Sight Reduction Navigation using stars, the moon and sun to work out your position in latitude. In order to navigate accurately you needed to know where you were in both latitude (North to South) and longitude( East to West). Latitude was relatively easy to determine, if you knew the coordinates of a celestial object, the position of the object in the sky, the local sidereal time, apply some spherical trigonometry then you can determine your latitude.

A Sextant
 Used to measure the angle between any two visible objects. Its primary use is to determine the angle between a celestial object and the horizon which is known as the object's altitude.

Longitude was a more difficult problem. Initially longitude position was determined by the positions of the Moon but the lines of longitude differed between countries and charts.  In 1675 the Royal Observatory was established at Greenwich, England and here accurate data on the Moon was slowly accumulated. In 1767 the publication of English Nautical Almanac eventually led to the universal adoption of the meridian of Greenwich as the prime meridian, i.e. a line of longitude, at which longitude is defined to be 0°. The next step was to have a reliable way to compare the time where you were, to the time at the prime meridian, an hour is equal to 15° of longitude, you couldn't rely on the Ship's Boy turning the sand glass. Even the most reliable pendulum clocks of the time were unable to cope with the movement of the ships, changes in temperature and humidity. In 1714 this led to the launching of a competition by Act of Parliament, with a  £20,000 prize, to be the first to construct a marine chronometer precise and accurate enough to  provide longitude to within half-a-degree (2 minutes of time).
Stepping on the the podium in first place was Lincolnshire carpenter and self-taught clockmaker John Harrison (read here about his struggle with the Board of Longitude to actually be awarded the full prize money, it took the intervention of the King and another act of parliament).

John Harrison's Marine timekeeper, H4 completed in 1759 with its very stable, high frequency balance,
it proved the successful design. It was based on the design of a watch rather than a clock.

His chronometers worked at sea! Captain James Cook took K1 a replica of H4 with him on his sea faring expeditions.

Click here to read  in more detail about the development of Navigation.

Visit the museum in Greenwich to see John Harrison's chronometers, if you want to see one of his early Clocks or his paper drawing of the movement of H.4, go to the Clock Makers Museum at the Guildhall, City of London, where there is a wonderful collection of early clock, watches and sundials. Entrance is free!

I don't wear a watch. I want my arms to weigh the same.

The words of Harry Hill. Anyone else out there not wear a watch? My husband has a bit of a collection, the most precious both in material and sentimental value is a watch left to him by his grandfather. Harvey Lewis was born in the 1890's, he grew up in the East End of London where he trained and qualified as a Ladies Master Taylor. Just before the WW1 he married and moved to North London.  During the war he was a bit of a wheeler dealer then after he established a flourishing tailoring business which he ran from his front room. The success of this lead to him rewarding himself with a Rolex Zebra Striped 9K Gold Prince Brancard wristwatch.

The Rolex Prince Watch

On October 1, 1927, the patent number 120849 was granted for a movement that was to be named Prince. The main advantage of the movement design was that, by placing the winding barrel and the balance at opposite ends of the watch, they could each be much larger. The Rolex Prince watch proved to be one of the most accurate wristwatches made. The accuracy comes from the very high quality balance wheel, which most unusually for a wristwatch used solid gold screws to add extra weight and therefore, momentum. The watch also had a very high quality finish to the whole escapement, even the wheels. All of these efforts went to ensuring the accuracy of the Prince. Rolex Prince with two dials is often referred to as a ‘doctors watch’ or ‘duo-dial’. The strap is a replacement however it still has the original gold plated pin buckle. The watch was given to Max, Harvey's only child, who hardly wore it and kept it in a safe for many years before passing it on to his younger son. Feel tempted to buy one? click here to make an offer.
Harvey also left some labelled coat hangers and wonderful wool fabrics that have since been made into suits.

Watches have become a fashion accessory and for some a status symbol, others - just need to know the time. Which has made me wonder when man first had the need to tell the time, just going to google that question.......It seems that our forebears invented methods to divide the day or the night into different periods in order to regulate work and for ritual/religious festivals. The lengths of the time periods varied greatly from place to place and from one culture to another. An Egyptian sundial from about 1,500 BC is the earliest evidence of the division of the day into equal parts, but a sundial couldn't be used at night so other methods such as water clocks (clepsydra), oil lamps and candle clocks were developed. Click here to read about sundials in detail and make your own - all very mathematical.
In 27 AD Hipparchus of Niceae, working in Alexandria, proposed dividing the day into 24 equinoctial hours. Equinoctial hours, are based on the equal length of day and night at the equinox, split the day into equal periods. However, ordinary people didn't adopt this for well over a thousand years. (The conversion to equinoctial hours in Europe was made when mechanical, weight driven clocks were developed). The division of time was further refined by another Alexandrian based philosopher, Claudius Ptolemeus, who divided the equinoctial hour into 60 minutes, using by the scale of measurement of ancient Babylon.
The first clock escapement mechanism appears to have been invented in 1275 and subsequently watches evolved from these portable spring-driven clocks. More detail to follow in future blogs.

If you get a chance to visit the The science museum you can see a collection of early watches there.