Presentation on theme: "The Science of Natural and Synthetic Diamonds The “Millennium Star” is currently the most valuable diamond on Earth... “priceless” (never been sold) It."— Presentation transcript:
The Science of Natural and Synthetic Diamonds The “Millennium Star” is currently the most valuable diamond on Earth... “priceless” (never been sold) It is insured for $100 million
Pure Carbon Minerals on Earth Diamonds & Graphite
Mineral -- Definition starts as follows… Naturally occurring, inorganic solids … Man-made made minerals not from a living organism, require the adjective thus “amber” which is a natural “synthetic” in front carbon-rich “pine sap” is the mineral name “organic” and is not a mineral. Research commissioned by the Diamond Trading Company shows that 94% of women prefer real diamonds to synthetic diamonds.
Diamonds may not be forever !!
Diamonds from Meteorite Impact The black diamonds known as carbonados ; ( get their name for their carbonized, or burnt, look) Some of the largest are at Canyon Diablo in Arizona …
How to Generate High Pressures Without Superman or a Meteorite Need a “mad” scientists and a “Piston-Cylinder” Machine
Nature Generates High Pressure by Burial deep in the Mantle of the Earth Lava erupts from the Pipe at a speed of Mach 5 and a temperature of 32 o Fahrenheit
“Blue Ground” - Kimberlite
Natural Diamond Mine in a Kimberlite Pipe Finding diamonds here is like finding a “needle in a haystack”
Diamond Mining & Exploration… The Pipe itself … or… Let water concentrate them.. Alluvial Diamonds Diamond has a high hardness (can’t be scratched) & high density making it “heavy”
Alluvial – Settle out of water in gravel beds
Brazil’s alluvial diamonds are hundreds of miles from the pipes… most of the pipes are “undiscovered” X-ray the gravel… diamonds will fluoresce in blue
Diamonds in Kimberlite Matrix Alluvial Diamonds Real Crystals Isometric “cubic” Often “Cleavage Fragments”
How can a “Cubic” Crystal become an Octahedral Cleavage fragment ? Start with “red” cube, break off each corner in yellow…. End ups with octahedral cleavage fragment…
Lieber & Solow is one of oldest clients of the DTC Diamond Trading Company in London. We are one of only a handful of industrial Sightholders worldwide. As such, we are able to consistently keep in inventory a full range of products. A full- time staff manufactures parcels of wire dies, dressing tools, coning tools, shaping tools, form tools and drill bits
Natural Diamond Crystal Are “Isometric” the most common pure shapes are….. Cube: Six sides “squares” Octahedron: Eight sides “triangles” Dodecahedron: Twelve sides “diamonds” Tetrahedron: Four sides “triangles” 1916 Goldschmidt’s 500+ drawings of Diamond Crystal Shapes….
1916 Goldschmidt’s 500+ drawings of Diamond Crystal Shapes….
Congo cube & Interpentration Twin
Multiple Crystal Shapes on a single Natural Crystal Cube “6” Dodecahedron “12” Octahedron “8”
Dodecahedron + Cube + Octahedron
Fine lines are etched into the dodecahedral faces,. Fine square/pits on the cube faces,. Triangles etched on octahedral faces.
Use “markings” to identify the shapes (forms)
Approx 20% of all mined diamonds are cut into gems, and the majority of the rest are used in Industry Natural uncut Diamond crystals are more of a rarity to be owned, for several reasons – they are highly valued as a cut stone, therefore it is difficult to obtain high quality natural uncut crystals outside of the gem trade, and they are often very small in size. Micromount $ cm … ¼ inch
The Oppenheimer Diamond At 254 carat (50 gm) this yellow natural octahedral crystal is the largest uncut diamond “crystals” in the world Discovered in 1964 the stone was presented to the Smithsonian Institution in memory of the late Sir Ernest Oppenheimer, who started De Beers. 1 inch
In Paris, Don Pedro Davilla (ca.1775), had a mere 16 diamond crystals in his enormous collection of over 8,000 total diamond specimens Paul Seel (1982) assembled the world’s largest collection of several hundred diamond crystals, each of which "illustrated some morphological fact" “ Aurora Collection” ( contains no diamond crystals)
Cut diamonds increase in value over 5x A 603 Carat Diamond comes from Lesotho - South Africa; named the "Lesotho Promise“ – sold for $12 million Lesotho Promise Diamond necklace cut from one stone into 26 jewels – $60 million
Diamonds are the most valuable commodity on earth based on dollar value per weight. The “Hancock Red” weighs only 0.95-carat, is purplish-red and sold for nearly $1 million. One carat is equal to oz. This is $14 ¼ million / oz. A diamond’s value can be more than 200,000 x greater than an equal weight of gold
A proper “cut” causes colors to appear Diamond has high dispersion … bends red light much more than it bends blue light
The Cullinan Diamond is the Star of Africa The world’s largest gem-quality uncut diamond was found in 1905 and had a weight of carats (approx 1.5 pounds). The fragment was cut into 105 gemstones, the largest is carats known as the Star of Africa, which is in the British Royal Scepter located in the Tower of London. The crystal morphology suggests that this diamond is in fact only a cleaved section of a larger octahedral crystal, which has never been found. The nine largest of the 105 pieces cut into gemstones
Law of Constancy of Interfacial Angles Contact angle for quartz pyramid is……………………………… 46 o Contact angle for diamond octahedron is …………….…. 70 ½ o
The “Golden Jubilee” at 546 carats The Unnamed Brown became the Golden Jubilee when King Rama IX of Thailand (also known as King Bhumibol Adulyadej the Great) was given the stone to the 50th anniversary of his coronation in Not many people in Thailand know that the Golden Jubilee is a diamond, as the government decided to tell its people that the Golden Jubilee is a large golden topaz
The previous record price paid for any polished diamond was $16.5 million for a carat stone, the Star of the Seasons, that was auctioned by Sotheby's in 1995, thus selling for about $165,000 per carat. “Priceless”…. Insured for over $100 million
The Millennium Star was part of the Splendor of Diamonds Exhibition at the Smithsonian Museum in Washington DC over the summer of 2003
Use of the “octahedral cleavage” as a diamond cutter… If your laser cut is not along the cleavage direction, when you hit the diamond for the first “cut” it will shatter.
Finding the “Octahedral Cleavage”
Piqué is a tiny black spot caused by undigested carbon inclusions (natts) within diamonds. Black material found within a diamond's internal cleavage planes is often graphite
Carbon piqué inclusions are sometimes removed by diamond enhancements such as laser drilling, which can leave their own types of unique inclusions.laser drilling
All of the microscopic diamond inclusion photography in this talk was generously contributed by the AGSL gemological testing laboratory in Las Vegas, Nevada, and is reproduced with their permission.AGSL
Feather “Inclusions” Partial octahedral cleavage forming around a stress point See triangles… See garnet causing stress Cleavage Plane = rainbow
Crystal Inclusions Mantle minerals captured by the diamond as it grew Chrome Diopside Pyrope Garnet Grossularite Garnet
Twinning Wisps Inclusions … bubble on surface between two twins Twinning Wisps will often create stress and cause a feature inclusion to form
Inscriptions are … embedded graphite in a laser cut Clarity… One of the 4C’s… in a cut stone… How to evaluate the inclusions….
Color in Diamonds result from inclusions of other elements & defects within the diamond lattice Yellow is the most common colour, and minute inclusions of nitrogen will give yellow hues Rare colors such as blue and pink are highly prized in cut gems… Boron will create a blue color Missing carbon atoms in the atomic lattice, called defects, will cause a diamond to turn pink or red. Artificial lattice defects…due to irradiation causes green and/or black diamonds.
Natural red & pink are most valuable Pink Diamonds from the Argyle-Mine Australia Chocolate Diamonds
Synthetic Diamonds…. High Pressure & High Temperature (HPHT) (maximum size about 6 carats) enormous energy costs Chemical Vapor Deposits (CVD) Growth rate of a millimeter / day on the surface of an (100) wafter
Chemistry of Chemical Vapor Deposits CVD Diamonds Chemical injected High temperature breaks Bonds and strips electrons C deposited on substrate as both graphite and diamond; but H+ etches the graphite off to form CH gas leaving just the diamond on the substrate
Fluoresence of CVD diamonds … is orange to red… not the blue of natural diamonds Typical anomalous double refraction due to strain caused by plastic deformation --‘Tatami Defect’ is found only in natural diamonds…. CVD diamonds are strain free
The Future … Turning unusual carbon forms directly to diamond
So, will a 10,000 Amp current heat a 0.001" graphite fiber to at least 3000º K at needed pressures? Graphite has a resistivity of microohm- cm at 20º C. If we have a one cm length of fiber, it will have a resistance of ( W- cm)(1 cm)/p( cm) 2 = 271 W. The rate of power dissipation will be (10,000 Amps) 2 (271 W) = 27.1 X 10 9 Joules/second. At 3000º K graphite has a heat capacity of 2.5 Joules/gramºK. Our hypothetical fiber contains 1.3 X grams of graphite. To raise its temperature from 295º K to 3000º K will require (2.5 J/gºK)(1.3 X g)(2705º K) = 0.09 Joules of energy. At a power level of 27 GW, this will take only 3.3 X seconds. No problem. I am convinced that this method of diamond synthesis of carbon fibers will work. Is Z-pinch the future? A recent posting on the diamond blog…
I’m afraid the numbers don’t lie Norton, We’re definitely nerds… that may be true Henry…. but we are very rich !! Modern Diamond Scientists
Exploring in North America for new diamond deposits
Where can you get Diamonds in N. America? In your dreams….. Not worth it….
Crater of Diamonds State Park Murfreesboro, Arkansas Thirty-seven acres of diamond producing “plowed” field within a single crater, is the only site in the world where diamonds are regularly found and is open to the public
Archean-age Rocks on the surface... vs … under sediments USA -- Unexplored diamond pipes are in the “Wyoming” Province
Over 400 Unexplored “potential” Diamond Localities in Colorado, Wyoming, & Montana Rocks in region must be early Precambrian in age … > 1,500 million years old Explosion pipe must be present… seen as depression lake without drainage
Over 400 Unexplored “potential” Diamond Localities in Colorado, Wyoming & Montana …. Rocks must be “brecciate” into pulverized fragments… blue ground helps A drop of acid on the soils will cause it to “fizz”…. Lots of carbonate causes a vegetation “anomaly”.. Iron Mnt. Colo.
Over 400 Unexplored “potential” Diamond Localities in Colorado, Wyoming & Montana …. You will find fragments (xenoliths)of mantle material – peridotite and eclogite – (olivine & garnet) You will find gem quality fragments of associated minerals…. red pyrope garnet = Cape Ruby green chrome diopside = Cape Emerald green olivine = Peridot
Diamonds are called 'ice‘ by many prospectors because its excellent thermal conductivity attracts heat. When touched to your lips, it will conduct heat away from your lips and give a sensation of feeling cool. 200x greater than copper Take a quartz crystal with you. A diamond will easily scratch the face of the quartz (don’t use “glass” because all associated minerals will scratch the glass). One of the easiest methods is to use a relatively inexpensive device marketed as a 'Diamond Detector' or 'Diamond Detective‘ at about $99, which measures the conductivity. Set up a small “grease board”: diamonds repel water and are attracted to grease Over 400 Unexplored “potential” Diamond Localities in Colorado, Wyoming & Montana …. How to “recognize” that diamond in the rough when you find it……
Iron Mountain, State Line, Sheep Rock districts of Colorado Kelsey Lake, Colo… waste dump (6.2 carat stone in 2003) Leucite Hills in SW Wyoming … diamonds found Twin Mountain Lakes, Wyoming is a major district of 50+ volcanic explosion crater found sitting within view of Interstate 80 west of Cheyenne Indian Guide district in Wyoming (west of Chugwater) Happy Jack There are explosion deposits south of Laramie Over 400 Unexplored “potential” Diamond Localities in Colorado, Wyoming and Montana 1996 – 2000
Chuck Fipke A short, absentminded Canadian geologist named Chuck Fipke, discovered diamonds in Lac de Gras, Northwest Territories, in 1991, he started the largest staking rush in North America since the great gold rush.Lac de Gras Nick-named "Stumpy" and "Captain Chaos"
The 3 “Commerical” Localities in 1998
Ekati and Diavik diamond mines at Lac de Gras on the Slave Craton became North America's major “commercial” diamond mines Diavik, on an island in Canada’s Northwest Territories, began production in 2003 (ice road trucker are used to move all provisions) The Ekati opened in 1998… There are 156 known kimberlites within the EKATI block of claims and 41 are known to contain diamonds