Detecting Her Likes And Dislikes

It may be evident that the love you have for your fiancée radiates from her glow being around you. You can’t help but secure that love you feel for her with something that may seem as priceless and unique as a diamond born millions of years ago, only to surface the earth and sparkle on her finger, complimenting her true beauty.

Over the centuries engagement rings have continued to make the statement for unity and everlasting love. If your quest has now become to buy your fiancée that special engagement ring that will captivate her heart, then you’re on the right track. We’ll help you avoid the pitfalls when shopping, and show you how to take advantage some of the tools made possible to educate you, and guide you on your quest.
What's Her Style?

First things first, take your fiancée to the mall or jewelry store in your local area, pretend your looking for a watch or gold chain, and watch her glide across the other side of the shop where the diamond rings are being displayed. Let her feed her curiosity, and/or try on a ring or two, or three (like in my case). Open your ears to the jeweler's lingo, listen for clues like ring size (fitting her finger), and the style of diamond she admires, whether that be brilliant round , emerald cut, Pear, Oval, Heart, etc. Does she like a solitaire diamond ring, or a three stone diamond ring? After walking away from the jeweler you should have gathered enough info on what type of diamond your fiancée desires. Now I'm not saying this method works for everyone. If you’re buying the diamond for yourself you would definitely visit the jeweler and ask all the questions that would concern you.
A Gaudy Diamond Ring May Be Tacky - How so?

Although most women would love to have a large diamond, remember that a larger diamond also creates the illusion of power, wealth and influence. To some women this may be uncomfortable to wear if they don't fit this stamina. Your fiancee may be humble with a smaller diamond which will not clash with her persona, something she may feel at ease wearing that is more humble to her soul, avoiding a gaudy yet risky to wear engagement ring also in fear of having it stolen.
Some agree that the bigger the finger the bigger the diamond, the smaller the finger the smaller the diamond otherwise the ring may once again look gaudy. Hench, those that have smaller fingers a 1ct diamond ring would look huge.

Facts About DIamonds

Diamond facts

* All diamonds are at least 990,000,000 years old. Many are 3,200,000,000 years old (3.2 billion years)

* Diamonds are formed deep within the Earth: between 100 km and 200 km below the surface.

Diamonds form under remarkable conditions!

o The temperatures are about 900 - 1300 C in the part of the Earth's mantle where diamonds form
o The pressure is between 45 - 60 kilobars (kB)
+ 50 kB = 150 km = 90 miles below the surface
+ 60 kB = 200 km = 120 miles below the surface
Diamonds are carried to the surface by volcanic eruptions.

The volcanic magma conduit is known as a kimberlite pipe or diamond pipe. We find diamonds as inclusions in the (rather ordinary looking) volcanic rock known as kimberlite.

NOTE: The kimberlite magmas that carry diamonds to the surface are often much younger than the diamonds they transport (the kimberlite magma simply acts as a conveyer belt!).

* Diamond is made of carbon (C), yet the stable form (polymorph) of carbon at the Earth's surface is graphite.

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* To ensure they are not converted to graphite, diamonds must be transported extremely rapidly to the Earth's surface.

It is probable that kimberlite lavas carrying diamonds erupt at between 10 and 30 km/hour (Eggler, 1989). Within the last few kilometers, the eruption velocity probably increases to several hundred km/hr (supersonic!).

* Diamond is the hardest material

Diamond is the hardest gem on MOHS harness scale and graphite (also made from carbon atoms) is the softest !! Given that both diamond and graphite are made of carbon, this may seem surprising.



The explanation is found in the fact that in diamond the carbon atoms are linked together into a three-dimensional network whereas in graphite, the carbon atoms are linked into sheets with very little to hold the sheets together (thus the sheets slide past each other easily, making a very soft material).

Diamonds occur in two general types of deposits world wide:

* volcanic pipes, also known as kimberlite pipes
* alluvial, or placer, deposits, which were formed by the erosion of diamond pipes over millions of years.

The earliest productive mines were in the Golconda region of India, particularly along the Kristna River. After 1725 this mining district was gradually eclipsed in importance by the diamond deposits of Brazil. Diamonds were first mined there along the Jequitinhonha River, in the Diamantina area of the state of Minas Gerais.

In 1867 a 21-carat stone was discovered on the banks of the Orange River near Hopetown, South Africa. A great diamond rush started, and new deposits were discovered that were more productive than any the world had ever known. Another major diamond resource was developed in the 1950s in the Yakutia region of the Soviet Union. By the 1980s the Yakutia and South African regions and the country of Zaire dominated the world's diamond market. The mineral has also been found in smaller amounts in numerous other places. In the United States the leading producers include Arizona, Nevada, and Montana, although the largest gemstones have been found in an eroded volcanic pipe in Pike County, Ark.
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For many years, microscopic diamonds have occasionally been noted in meteorites; they were attributed to high-speed collisions in space or with the Earth. In 1987, however, following the discovery of many more such diamonds, the theory was developed that they are the product of ancient supernova explosions of giant stars.

In recent years, diamonds have been found in unusual metamorphic rocks that were subjected to very high temperatures and pressures.


HOW RARE ARE DIAMONDS?

· How many grams do you need to mine to get 5 grams of diamonds?

(5g/1000 kg) @ 1000 g/kg = 5 g /1,000,000 g!

BUT only 20 % are gem quality (80 % of these are sold in a 'managed selling environment') and the remainder are used for industrial purposes (this material is known as 'bort' or 'carbonado' (carbonado is finer)).


CHARACTERISTICS OF DIAMOND:

· Hardness = 10

· Crystal System = cubic

· This is what crystals look like before they are faceted: note their natural octahedral shape!

Uncut diamonds are also found in cubic forms

· Diamond has four good cleavages, thus diamonds tend to cleave on impact

· Other diagnostic properties.


Other issues: Treatment, simulants, synthetics

(1) TREATMENTS:

* (a) filling of cracks

Surface cracks and cleavages reaching the surface: often with a glass-like material

Identification: optical microscope examination:

+ =greasy appearance
+ =flash effect
+ =bubbles

Problem: Filling does not always resist polishing and cleaning

* (b) drilling of inclusions
+ Drilling inclusions involves use of a laser.

Solutions can be poured into the resulting "hair-width" diameter hole to bleach colored inclusions.

* (c) irradiation

Irradiation is used to change the color of the diamond. A common color produced by irradiation is green.

Early attempts: beginning of 20th Century: diamonds exposed to radium - the problem was that the diamonds remained radioactive!! However, modern irradiation treatments do not produce radioactive stones.

Irradiation involves the use of devices such as:

o (1) linear accelerators

o (2) gamma ray facilities

o (3) nuclear reactors

Detection of irradiation treatment:

Electron irradiation only changes the surface of the stone. Thus, it produces a concentration of color where the gemstone is thin. For example, electron irradiation produces a color concentration at the culet or keel line of the faceted gem

(2) SIMULANTS

Simulants - simulate the appearance of diamond

The distinction between a synthetic diamond (man-made diamond consisting of carbon atoms arranged in the typical diamond structure) and a diamond simulant (not a carbon compound with the diamond structure) is VERY important!!

In order of increasing R.I., the most common simulants are:

1. YAG = yttrium aluminum garnet
2. GGG = gadolinium gallium garnet
3. CZ = cubic zirconia
4. Strontium titanate
5. diamond.

This rhyme can be used to memorize the common diamond simulants in the above order:

You go crazy staring at diamonds.

Again: Simulants (look alsikes) differ from synthetics (synthesized by humans!) !!!!

Simulants are distinguished from diamonds using measurement or observation of various properties, such as:

o R.I.
o "Read through effect"
o Dispersion
o Hardness
o Specific Gravity
o Reflection pattern
o Shadow patterns

Note: not all diamond simulants have been around for the same length of time!

(3) SYNTHESIS (Details on gem synthesis)

Synthetic diamonds are often yellowish in color (rarely used for gem purposes, more commonly used as diamond grit for industrial purposes. Modern synthesis of thin film diamond has other industrial applications).

A 5 mm diamond (0.5 carat) takes over a week to grow. Synthesis requires:

* high pressure
* high temperature
* a special apparatus

Synthetic diamonds can sometimes be distinguished from natural diamonds by the presence of flux inclusions (Ni, Al or Fe).

Also see Other Blog on Diamond: Diamonds Exotica

Properties Of Diamond

A diamond is a transparent crystal of tetrahedrally bonded carbon atoms (sp3) that crystallizes into the diamond lattice which is a variation of the face centered cubic structure. Diamonds have been adapted for many uses because of the material's exceptional physical characteristics. Most notable are its extreme hardness and thermal conductivity (900–2,320 W·m−1·K−1),as well as wide bandgap and high optical dispersion.Above 1,700 °C (1,973 K / 3,583 °F) in vacuum or oxygen-free atmosphere, diamond converts to graphite; in air, transformation starts at ~700 °C. Naturally occurring diamonds have a density ranging from 3.15–3.53 g/cm3, with very pure diamond typically extremely close to 3.52 g/cm3.

Hardness

Diamond is the hardest natural material known, where hardness is defined as resistance to scratching.Diamond has a hardness of 10 (hardest) on Mohs scale of mineral hardness. Diamond's hardness has been known since antiquity, and is the source of its name.

The hardest natural diamonds in the world are from the Copeton and Bingara fields located in the New England area in New South Wales, Australia. These diamonds are generally small, perfect to semiperfect octahedra, and are used to polish other diamonds. Their hardness is associated with the crystal growth form, which is single-stage crystal growth. Most other diamonds show more evidence of multiple growth stages, which produce inclusions, flaws, and defect planes in the crystal lattice, all of which affect their hardness.It is possible to treat regular diamonds under a combination of high pressure and high temperature to produce diamonds that are harder than the diamonds used in hardness gauges.

The hardness of diamonds contributes to its suitability as a gemstone. Because it can only be scratched by other diamonds, it maintains its polish extremely well. Unlike many other gems, it is well-suited to daily wear because of its resistance to scratching—perhaps contributing to its popularity as the preferred gem in engagement or wedding rings, which are often worn every day.

Industrial use of diamonds has historically been associated with their hardness; this property makes diamond the ideal material for cutting and grinding tools. As the hardest known naturally occurring material, diamond can be used to polish, cut, or wear away any material, including other diamonds. Common industrial adaptations of this ability include diamond-tipped drill bits and saws, and the use of diamond powder as an abrasive. Less expensive industrial-grade diamonds, known as bort, with more flaws and poorer color than gems, are used for such purposes.

Diamond is not suitable for machining ferrous alloys at high speeds as carbon is soluble in iron at the high temperatures created by high-speed machining, leading to greatly increased wear on diamond tools when compared to alternatives.

These substances can scratch diamond:

* Some diamonds are harder than others.
* Nanocrystalline diamond aggregates produced by high-pressure high-temperature treatment of graphite or fullerite (C60).
* Cubic Boron nitride (Borazon)
* A hexagonal form of diamond called lonsdaleite, which is theoretically predicted to be 58% stronger than diamond.

Electrical conductivity

Other specialized applications also exist or are being developed, including use as semiconductors: some blue diamonds are natural semiconductors, in contrast to most other diamonds, which are excellent electrical insulators.The conductivity and blue color originate from the boron impurity. Boron substitutes for carbon atoms in the diamond lattice, donating a hole into the valence band.

Substantial conductivity is commonly observed in nominally undoped diamond grown by chemical vapor deposition. This conductivity is associated with hydrogen-related species adsorbed at the surface, and it can be removed by annealing or other surface treatments.

Toughness

Toughness relates to a material's ability to resist breakage from forceful impact. The toughness of natural diamond has been measured as 2.0 MPa·m1/2, and the critical stress intensity factor is 3.4 MN·m−3/2. Those values are good compared to other gemstones, but poor compared to most engineering materials. As with any material, the macroscopic geometry of a diamond contributes to its resistance to breakage. Diamond has a cleavage plane and is therefore more fragile in some orientations than others. Diamond cutters use this attribute to cleave some stones, prior to faceting.

History Of Diamond

The name diamond is derived from the ancient Greek ἀδάμας (adámas), "proper", "unalterable", "unbreakable, untamed", from ἀ- (a-), "un-" + δαμάω (damáō), "I overpower, I tame".However, diamonds are thought to have been first recognized and mined in India, where significant alluvial deposits of the stone could then be found many centuries ago along the rivers Penner, Krishna and Godavari. Diamonds have been known in India for at least 3,000 years but most likely 6,000 years.

Diamonds have been treasured as gemstones since their use as religious icons in ancient India. Their usage in engraving tools also dates to early human history.[ Popularity of diamonds has risen since the 19th century because of increased supply, improved cutting and polishing techniques, growth in the world economy, and innovative and successful advertising campaigns.

In 1813, Humphry Davy used a lens to concentrate the rays of the sun on a diamond in an atmosphere of oxygen, and showed that the only product of the combustion was carbon dioxide, proving that diamond is composed of carbon. Later, he showed that in an atmosphere devoid of oxygen, diamond is converted to graphite.

The most familiar usage of diamonds today is as gemstones used for adornment, a usage which dates back into antiquity. The dispersion of white light into spectral colors is the primary gemological characteristic of gem diamonds. In the twentieth century, experts in the field of gemology have developed methods of grading diamonds and other gemstones based on the characteristics most important to their value as a gem. Four characteristics, known informally as the four Cs, are now commonly used as the basic descriptors of diamonds: these are carat, cut, color, and clarity.

Diamond | The Precious Stone