Persian Treasures - Empress Farah Deeba's Tiara

Farah Deeba's favorite Tiara

This tiara was also designed by Harry Winston, the New York jeweller, for the occasion of the marriage of Empress Farah Deeba and Reza Shah Pahlevi in 1958. It was considered to be Farah's favorite tiara, since she was often seen wearing it on formal occasions, such as her on visit to the United States and Canada in 1965. The lower band containing diamonds which is shaped like a heart, is built of platinum. There are two rows of yellow, pink and clear diamonds on top of it. There are seven large emeralds framed by diamonds on very top of the tiara. The gems used in this tiara are a combination of the old and new. The brilliant-cut diamonds were probably re-cut in the 19th century from loose Indian diamonds which were in the treasury. The emeralds are probably from South America, though they were cut sometime before Nader Shah's campaign in India. The diamonds surrounding the emeralds are probably from South Africa. The largest emerald, located in the center of the top row, is 65 cts. and the smallest ones on the ends of the row are 10 cts. each. The two largest diamonds are approximately 15 cts. each.

Persian Treasures - The Kiani Crown

Kiani Crown

The Kiani Crown was used during the Qajar dynasty. Reza Shah, the founder of the Pahlavi dynasty, had his own crown designed but the Kiani crown was present during his coronation. The crown itself is made of red velvet which has thousands of gems set onto it. Fathali Shah is often shown in paintings wearing a similar crown - it is not known whether there were a number of crowns in use at the time which looked similar, or whether the artists simply portrayed the same crown in different ways. The Kiani crown has about 1800 pearls sown onto it, each from 7 to 9 mm. in diameter. There are approximately 300 emeralds set on the crown, the largest of which is about 80 cts. There are also about 1800 rubies and spinels on the crown, the largest of which is 120 cts. The largest diamond is 23 cts. The total height of the crown is 32 cm. without the aigrette, and the total width is 19.5 cm.

Persian Treasures - The Pahlavi Crown

The Pahlavi Crown

This crown was used by Reza Shah, the founder of the Pahlavi dynasty, in his coronation on 25 April 1926. His son, Mohammad Reza Shah Pahlavi, the last Shah of Iran, also used the crown in his coronation on 26 Oct. 1967. The crown was designed and built by a group of Iranian jewellers, under the supervision of Haj Serajeddin, the famous jeweller who had been in the employ of the Amir of Bokhara and had later emigrated from the Soviet Union to Iran. The stones were selected from loose stones in the treasury. The crown made of red velvet, gold, and silver. It has a total height of 29.8 cm. and has a width of 19.8 cm. It weighs 2,080 grams. The are 3,380 diamonds employed on the crown, totalling 1,144 cts. The largest is a brilliant-cut yellow diamond of 60 cts. which is located in the center of the front jewel sunburst. There are also 369 perfectly-matching natural pearls in three rows on the crown. Of the 5 emeralds, totalling 200 cts., the largest is approximately 100 cts. The largest sapphire is 20 cts. The design of the crown incorporates a motif of the Sassanid dynasty, which ruled over the Persian Empire from the 3rd through the 7th centuries AD.

Persian Treasures - Jewel Studded Globe

Jewel-Studded Globe

The most magnificent globe in existence, it has a total height of 110 cm. and a diameter of 45 cm. and is covered with over 51 thousand gemstones. The seas and oceans are shown with emeralds. Land masses are mostly displayed in rubies and spinels. Iran, Britain, France, and parts of South Asia are shown in diamonds. The base is constructed of wood, covered with a layer of gold. Approximately 35 kilograms of pure gold is used in the globe. According to legend, Nasseridin Shah (1848-1896) ordered the construction of the globe to help keep track of the loose gemstones in the treasury. The largest ruby used in the globe is approximately 75 ct. The largest spinel is approximately 110 cts. The largest emerald is approximately 175 cts., the largest sapphire is approximately 34 cts, and the largest diamond is approximately 15 cts.

Persian Treasures - Darya e Noor (Sea of Light)

Diamond of Darya-e Noor (Sea of Light) One of the few largest diamonds in the world;it weighs 186 cts.

Cullinan 1

One of the largest diamonds in the world (530 carats).

Topaz

What it takes to be Ideal CutIdeal cut diamonds come from raw diamonds that have been cut to specific standards.
When seeing a title such as "ideal cut" one may wonder as to why all diamonds are not cut to become ideal cut diamonds. There are numerous reasons for this, including the properties of the natural raw diamond, monetary reasons and aesthetics.

Zircon (Imitation)

For one thing, most raw diamonds cannot be cut for use as jewelry-quality diamonds, much less be cut to ideal cut ratios. Out of the few raw diamonds found that can be utilized for jewelry, only a small percentage of these have the physical properties to be cut to the ideal cut round brilliant proportions. This is not to say that they are the most rare of diamonds, as they are not, but simply to note that due to such variables as naturally occurring inclusions (flaws within the diamond's crystalline structure, such as spots of other minerals, and cleavage lines) it is impractical, if not impossible, to cut all jewelry quality raw diamonds into ideal cut round brilliant diamonds.

Zircon

Another reason for not using the ideal cut round shape for all diamonds is simply that the ideal cut is not ideal for all people and all occasions. The ideal cut emphasizes particular aspects of the diamond, such as the brilliance and fire. However, these characteristics are primarily brought out in bright, modern lighting. The more romantic lighting of candlelight and gaslight is more complementary to older diamond cuts, such as the rose cut, and the step cuts, such as the emerald cut. While round diamonds, ideal cut or not, enjoy a high level of popularity diamonds themselves are as unique as the people who own them. Even though the round ideal cut is a popular choice, it is by no means the standard.
In short, not all diamonds are ideal cut diamonds because not all can be, not all are monetarily able to be, and not everyone wants them.

Blue Zircon

There are also monetary reasons for not choosing ideal cut diamonds. When an experienced diamond
cutter is examining a raw stone of jewelry quality, the cutter looks for the flaws, but also for
the cleavage points. It is at these cleavage points in the raw stone that the cuts must be made,
or the entire diamond could shatter. An experienced cutter can assess what diamond shapes can be
brought out of a raw diamond, and has to take into consideration points such as which shapes are
being asked for by the owner of the diamond, as well as which shapes are the most feasible to cut
and sell. While ideal cut rounds are popular, they can often waste an enormous quantity of the
raw diamond in the cutting process if the cleavage points do not accommodate the round ideal cut
shape. Even when round brilliants can be brought out of the raw diamond, the ideal cut can not
only require more time, but it could also reduce the carat weight of the finished diamond, thus
reducing its value.

Red-Blood Ruby!

The world leader of diamond production is still South Africa. For the
past century and a half, South Africa has been the world leader in
producing and transporting diamonds. It is through South Africa's mass
production, distribution and shrewd business decisions that they remain
the world's diamond leader. It is in South Africa that the diamond
industry's leader, DeBeers is located. Through their ownership of the
primary and largest diamond mines in the world, DeBeers is able to
control much of the diamond industry. However, diamond deposits in
Russia's Siberia region and the newly discovered deposits in
Australia's Northern and Western Territories are closing the historic
diamond production gap.

Ruby Ring

South America is also still producing diamonds in large quantities,
almost 300 years since they were first discovered there by western
interests. Brazil and Venezuela are the two major diamond producing
nations in this area. Newly available technology has allowed more
diamond deposits to be mapped, giving this area the ability to remain
strong in diamond production.

Emerald-Cut Alexandrite (simulated)

Canadian diamonds gained a strong foothold in the diamond trade when
the politics met up with geology. As large diamond deposits were found
in the Canadian Northwest Territories in the 1990s it was concurrently
discovered that the nations of Sierre Leone, Angola and The Republic of
Congo were using their diamond sales to fund civil war. The branding of
such diamonds as "conflict diamonds" gave the new Canadian mines the
ethical upper-hand, and so helped to bring Canadian diamonds to the
forefront of diamond production. The Canadian diamond mining industry
has strict regulations in place, documenting all of the diamonds
produced from their mines. In this way these diamonds are assured of
being Canadian diamonds, including having a polar bear mark inscribed
on the diamonds in order to brand them.

Aquamarines (simulated)

Today diamond mines are found throughout the world. The current leading
nations in diamond production are still found in Africa, but other
nations are beginning to produce diamonds in the volume in which
African nations have been operating for the past century and a half.
Three of the world's leading diamond producing countries are in Africa:
Botswana, Namibia and South Africa. The non-African leaders in diamond
production include Canada, Brazil, Venezuela, Russia, and Australia.

Where do Diamonds Come From..

Where Diamonds Come From

Diamonds are found in alluvial deposits in diamond mines in places such
as Botswana, Namibia, Canada, Brazil, Venezuela, Russia and Austrialia.
Diamonds were first discovered in alluvial deposits in southern India
about the 9th century BCE, and for centuries India remained the world's
primary source of diamonds. This changed in the 18th century with the
discovery of large diamond deposits in Brazil in 1725. Over a century
later diamonds were discovered in South Africa, and so began the
leadership of South Africa in the diamond trade.

Black Pearl

Egyptian Emerald

Emerald Cut Diamond
The Emerald cut diamond is a popular diamond cut with it's unique emerald cut shape and step cut facets.
The "emerald" cut of diamond is another square or rectangular shaped diamond. As opposed to the brilliant cut, however, with its triangular or four sided diamond cut facets, the "emerald" cut of diamond has step cut facets. The term "step cut" refers to the step-like look of the facet cuts.
This type of facet appears in long plate or plane-like facets, resulting in a more mirrored-type of effect, rather than the deep fire or shining brilliance of other diamond shapes. The emerald requires a diamond of higher quality of color and clarity than required with other shapes. This is due to the fact that scratches, inclusions and other impurities are more easily noticed with this bold type of cut. The emerald cut of diamond has an elegance and old world charm not found in brilliant styles.
It tends to have 50 to 58 facets, and a length to width ratio of 1.5-1.7 to 1. As with other square and rectangular shapes, the Emerald cut shape can be cut to be more square, to flatter the longer fingers, or more rectangular, thus flattering shorter fingers with the appearance of greater length. It tends to be 20% to 33% less expensive than round brilliants of the same weight, as is also the case with other square or rectangular shaped diamonds. The Emerald cut shape of diamond is linked to organized, resourceful, disciplined and decisive personalities.

CROWN OF CORTEZ EMERALD

CROWN OF CORTEZ EMERALD 306 carat Colombian Emerald From Louis XV’s World Famous Gem Collection Important 306 carat Colombian Emerald surrounded by 3.33 carats of the finest Diamonds in 18K white gold. The Crown of Cortez, also known as the Isabelle Stone, is one of the largest gem quality Colombian Emeralds in the world.

Emerald and Diamonds

Light Leakage

The term light leakage refers to the loss of light within the diamond. When properly cut, a
diamond will exhibit fire (resulting from the proper cut of the crown), brilliance (resulting
from the proper cut of the pavilion), and scintillation (resulting from the proper placement, or
symmetry and alignment of a diamond's facets). Scintillation is the actual play of light within
the diamond itself. Should any of the elements involved be cut incorrectly, resulting in poor
symmetry, poor brilliance, poor fire or a combination of the three, light will exit the stone at
one of the sides, rather than reflect and refract within the stone, exiting through the table.

Facet Shapes and Descriptions

Bezel

The bezel facet is the name for 8 kite-like facets that are cut into the crown of a brilliant
round cut diamond.

Kite

This is a facet that has been angled with four sides so as to best create the brilliance and
luster of diamond. This type of facet is most commonly associated with the brilliant cut of
diamond.

Rectangular

The next common type of facet is the long rectangular facet. This long facet is the facet that
one sees when looking at a step-cut diamond, such as an emerald cut. The long, wide plane created
by the use of the rectangular facet allows for a warm glowing play of light in and on the
diamond.

Star

The star facet is a triangular facet. There are 8 of these facets on a brilliant cut diamond and
they are found on the upper crown.

Ruby, Emerald & Pearl Set from Jagdamba Pearls

Girdle

The girdle of the diamond is the name for the widest portion of the
diamond. The diamond's diameter is measured at its girdle. The common
practice today is to facet the girdle itself, although these facets are
not included in the diamond's final facet count. As long as the girdle
is not described as extremely or extra thin or thick the girdle has no
effect on the stability of the diamond.

Depth

A diamond's depth is the measured height of the entire diamond.
Measuring from the top of the diamond (the table) to the bottom of the
diamond (the culet), the depth of the diamond helps to set the ratios
for the rest of the diamond's cut.

Culet

The culet is the bottom of the diamond and the diamond's smallest
facet. The culet has tremendous effect on the rest of the diamond in
that a properly formed culet will allow the light that has entered the
diamond to most effectively exit through the diamond's table and
re-enter the eye. A culet that is cut too large can cause a detrimental
effect in the diamond's light display. The overly large culet can cause
the light to leak out from it, thus causing the diamond to appear to
have a hole within it. The culet needs to be small enough, and within
the correct ratio to the rest of the diamond's anatomy to allow the
light to reach it and be refracted back within the diamond and
reflected back out of it. It is not uncommon for a diamond to have no
culet, and instead have the pavilion come to a point. There is no right
or wrong to having or not having a culet.

The Emerald Buddha Statue in Thailand!!!

Table

The largest facet of the diamond. This is the facet that sits at the
top of the diamond, and serves as the main entrance and exit point for
light.

Diameter

The measurement of the width of the diamond at its widest point
(girdle).

Crown

The crown refers to the part of the diamond from the girdle up. This
means that the section of the diamond from the widest point to the top,
or table, of the diamond is the named the crown.

Pavilion

The pavilion is the counterpoint of the crown in that it is the bottom
portion of the diamond. From the girdle, or widest section, of the
diamond to the bottom (or culet) is referred to as the pavilion.

Anatomy of a Diamond

Basic Anatomy of a Diamond

Important parts of the diamond anatomy include facets, table,
diameteer, crown, culet, pavilion, girdle and depth.

It is useful to understand the anatomy of the diamond. Like a human
body, each part of the diamond has a specific name, and knowing these,
and having a working understanding of what each part contributes to the
diamond as a whole, will help to assist you in purchasing a beautiful
diamond.

There are eight basic parts in the diamond anatomy. These are: Facets,
Table, Diameter, Crown, Pavilion, Girdle, Depth and Culet.

Facets

These are the flat planes that form the outer face of the diamond. Each
facet is angled, shaped and cut in order to produce a particular light
effect for the diamond and to most effectively reflect the inner
crystalline structure of the diamond. The facets are designed to allow
light to reflect off of, enter into, pass through and exit the diamond.
The arrangement of the facets is designed to allow light to enter
(normally through the table), refract within the diamond itself
(producing its "fire"), to exit the diamond (again, through its table)
as well as reflecting light directly off of the diamond's surface.

Ruby

The broad, flat-faceted step cut nature of the Asscher allows for
tremendous luster, but it will also illuminate any flaws. It is for
this reason that when choosing the Asscher, as with the emerald cut, it
is best to use stones of high quality in order to ensure that the
diamond has the greatest, unadulterated luster and shine. The Asscher
Diamond Company has recently resumed production of this bold cut. This
is definitely a cut of diamond for those who wish to express a sense of
elegance and beauty.

The British Crown!

The Asscher is a distinctive diamond, with a number of unique
identifiers. When choosing the setting for an Asscher, it is important
to make certain that the blocked corners are not hidden. It is these
blocked corners that add to the unique quality of the Asscher cut
diamond. Yet another of the singular aspects of the Asscher is found in
the shape and faceting of its pavilion. The pavilion is faceted in a
"scissor cut" fashion, in which the step cut is used to facet the
pavilion down to the culet.

Onyx

Like the emerald cut, the Asscher cut has large step-cut facets.
However, its facets tend to be larger than those of the emerald cut,
and its shape tends toward the square as opposed to the rectangular.
With its deep pavilion, faceted culet, high crown and small table, the
Asscher was designed to do more than just highlight larger stones. The
Asscher is designed to bring out their inner fire, while its small
table and high crown bring out more fire and scintillation than the
similar emerald cut. The Asscher has an ideal length to width ratio of
1 to 1.

geMMs

Asscher Cut Diamond

Information and history of the asscher cut diamond.
A 57 facet diamond, the Asscher cut diamond was developed at a time
when the round brilliant diamond was the common diamond shape. The
Asscher shaped diamond is named for its creator, Joseph Asscher, owner
of the Amsterdam based diamond company, the Asscher Diamond Company.
The Asscher cut was developed in 1902, coming in the beginning of the
Art-Deco movement that embraced and championed the straight lined
geometric form. Its square, step cut shape was the forerunner of the
later emerald cut shape of diamond.

Gemacious Tile!

There are some problems in using the Rapaport Report as your sole means of determining a
diamond's price range. One of the most obvious of these is that the report does not take an
individual diamond's unique characteristics into account. While it does account for the clarity,
color, the carat weight and certain other important aspects, this can hardly show the entire
picture. The report cannot tell you if a particular diamond has a cut that is amenable to your
personal tastes, nor can it account for the reflection of the diamond's clarity and color, once
set and sitting on your finger. In the end, it is useful to be familiar with the Rapaport Report,
but it should not be a strong deciding factor in your choice of diamonds. Use it simply to make
certain that you know what price range you should expect, and then look for the dealer who offers
their diamonds at a discounted price from that found in the Rapaport Report.

Amethyst and Diamonds

The Rapaport Report: This is a monthly-published diamond trade paper that offers current
per-carat pricing for diamonds. This diamond price report arrives at diamond pricing based on
color, clarity and carat weight. Using the pricing guide will give you an idea of the current
rate of a particular weight and color of diamond. What it cannot give you is an accurate price
for an individual diamond. This is merely a tool for those in the industry to have an idea of
what the approximate price for a particular type of diamonds is, and using it will allow you to
know the price range that you should expect to see.

Carat Expense Guide

Carat Expense Guide There are many factors to take into account when you are looking into buying a diamond, and the
carat weight is one of the most important. Within the diamond industry, carat weight is priced
through a number of factors, including the color and clarity as weighed against, and with,
various carat weights. All of this is published in the Rapaport Report, and diamond dealers use
this as a price guide for the per carat price for diamonds.

Ring Ring

Carat weight plays an important role in the pricing of your diamond, but it should not be the factor that outweighs all others. Each factor should be weighed alongside all others, but carat weight is the first that you can easily decrease in, without sacrificing the overall appearance of the diamond. In the end, the primary function of the diamond is an issue of aesthetics: you want the most beautiful diamond you can attain. It should be towards this goal that you assess all of the factors involved, in order to achieve the balance that will provide you with the diamond that will prove to be the perfect diamond for you.

Diamond Vase!

Another important point to be aware of is the factor of cut-off carat weights. These are also known as 'expense points' and having familiarity with them can not only save you money, but will also allow you to either reach or come close to the carat weight that you desire. Expense points refer to cut off points in carat weight where the cost can rise or decline exponentially. These points are at certain carat weights, such as the following: .50, .75, .90, 1, 1.5, 2 and so on. By staying just below these points, you can have a diamond that is negligibly less in weight, but notably less in expense. What this means is quite simple. If you are looking for a one-carat diamond, rather than choosing a diamond of one-carat or slightly larger choose a diamond that falls just below one carat, such as a .95 diamond. There will be no identifiable difference, especially once the diamond is set, and you could save a large amount of money.

Water Blues...

As you are deciding on your carat size, remember that the heavier diamonds are not necessarily better than smaller, less weighty diamonds. A smaller diamond with excellent cut, clarity and color will be far more impressive and arresting to the eye than a diamond with a large carat weight that has a poor cut, clarity and/or color. To illustrate the size factor further, think of what you would find more impressive in a car: a large, clunky Oldsmobile, or a small, sleek, Corvette? The same goes for diamonds. There are times when bigger is better, but unless you can afford to have all of the factors going up in relationship with the diamond's carat weight, you are better off choosing the cut, clarity and color of the diamond that you want, and then choosing the carat weight that you can afford.

Sapphire and Diamonds

The grain is the system of weight that was based on, simply enough, the wheat grain (or the barley grain in some ancient cultures). The grain was the equivalent of 1/4th of a carat, or, more simply, one carat equaled approximately 4 grains. From this use of the grain, you can see that the ancients understood the need for a quantifiable and standard system of weight. The tiny weight measurements involved with the grain further demonstrates their understanding of the need for weight that could accurately and consistently give a weight measurement for diamonds.

Glossy!!!

Another term of weight measurement that may be confusing is the term "Troy". The "Troy" is a measurement of weight that got its name from the French city of Troyes, which became an important trade city during the Middle Ages. The Troy unit of measurement was primarily used for precious metals, drugs and precious gems, such as diamonds. One Troy ounce is the equivalent of 31.1035 grams, or 480 grains.

Carat Equivalents

The following table will help to further illustrate the carat in comparison to other measurements of weight:
1 carat = 200 milligrams

1 carat = 1/5th gram

1 carat = 0.20 grams

1 carat = 100 points

1 carat = 4 grains Troy

1 carat = 0.007 ounce

141.7 carats = 1 ounce

Oceanic Blue

To place a carat next to a measurement scale most of us are familiar with, a carat is equivalent to approximately one seven thousandths of an ounce. This one relationship of two different types of weight measurement immediately demonstrates the small sizes that are being discussed when one is speaking of diamonds. To put a little more perspective on this, the largest rough diamond ever found, the Cullinan diamond from the Premier mine in South Africa, was an enormous 3,106 carats prior to cutting. This is a gigantic diamond, yet it is the equivalent of roughly three and a half pounds. Looking at it in such a light, you can see that even an enormous diamond, worth millions of dollars, is still fairly light in comparison to other precious commodities.

Colors of Life and...

"Points" is another term that you will hear to describe the weight of a diamond. The term "points" is used in the diamond industry to indicate diamond measurements that are lower than one carat. In the points measurement, one carat is divided into 100 points. Basically, if you are looking at a half-carat diamond, you may hear it being described as a 50-point diamond. Using the term '50 points' is simply another way of saying that the diamond is a 'half-carat' or 0.50 carats.

Blue's ma favorite color!

While it is important to be aware that the carat is the measurement of weight for diamonds, this does not provide a useful means of understanding carat weight in relation to other weights. It is simple to understand that a heavy diamond is not going to be heavy in relationship to most items that we are familiar with handling daily, but this doesn't give you a good feel for the weights that you will be dealing with when you are looking into diamonds. This is all the more reason to have a good understanding of the relationships between carat weight and how you can better identify the rough value of a diamond through sight and feel.

Untitleable!

It is the rarity of large diamond rough that is one of the primary reasons not all diamonds are ideal cut, as diamond cutters use the maintenance of carat weight as their primary motivation when cutting a diamond, and the ideal cut round is extremely wasteful. It is also useful to note that due to the effect of traveled light distance on diamonds, larger diamonds can often appear to be more brilliant than smaller stones. This is due to the greater prismatic effect resulting from the additional distance the light has to travel within the diamond.

Diamond in Rose

The exponential rise of the per-carat price in the diamond is a result of the fact that the rough for the heavier diamonds is rarer than the rough for smaller diamonds. Due to this, the heavier a diamond is, the exponentially greater the per-carat price will be. The aforementioned one-carat diamond might be priced at $7500 per-carat, whereas the comparable two-carat diamond could be $10000 a carat, or $20000 for the whole diamond. Meanwhile, a three-carat diamond of comparable characteristics could have a $15000 per carat price or a total carat weight price of $45000 for the entire diamond. It is for this reason that oftentimes if you are looking for a large total carat weight for the diamond piece, such as a diamond engagement ring, the best choice might be to have a multiple stone setting, as each stone has its own per-carat price.

Ruby Diamonds!

Be also aware that while a diamond is priced in great part based on its carat weight, it is not simply priced on the whole diamond weight. Diamonds are priced on a per-carat pricing system. This means that if a diamond is 3 carats, the cost of the diamond is based on the cost of each carat in the diamond added together, also known as the total carat weight. The cost per-carat is not stationary as you go up in carat size either. For example, if a one-carat diamond were priced at $7500 a carat, its total carat price would be $7500. One might think that a comparable diamond of two carats, with all other factors being equal, would also be $7500 per carat, with the total carat price being $15000. This is not the case. A diamond's per-carat price goes up exponentially based on the carat cost points on the diamond pricing report.

Aren't these a Beauty!

It is important to be aware that while the term carat refers to a diamond's weight, it does not refer to its dimensions or shape. The carat weight of a diamond can have an effect on its dimensions and shape, but neither the dimensions nor the shape is wholly dependent on the carat weight. For example, you could find yourself looking at two diamonds that look equal in size as you look down upon them. This does not mean that they have the same carat weight, however. A diamond can be cut to look larger than it is, through increasing its diameter and decreasing its depth, or through other cut techniques. The term carat is used to reference the diamond's actual weight, nothing more and nothing less.

Carat

What is a Carat?

Basic information about the carat for diamonds, such as carat weight.
All precious commodities have a system for giving the weight of the items, and this is no different for precious gems such as diamonds. While the cut of a diamond arguably has the greatest impact on the overall desirability of a diamond, the carat has the heaviest impact on its pricing. This is due to the fact that carat refers to the actual weight of the diamond and it is a diamond's weight that is one of the primary indicators for how rare a diamond is. Simply stated, the heavier a diamond is, the more rare it will be and thus the more expense.

Ammolite Jewelry

Diamonds

Compressive Strength: Diamond was once thought to be the material most resistant to compression (the least compressible). It is the material that scientists use to create the greatest pressures when testing matter. However, the rare metal Osmium has recently been shown to be even less compressible (although it is not as hard as diamond). Diamond has a bulk modulus (reciprocal of compressibility) of 443 GigaPascals (GPa). The bulk modulus of the metal osmium has recently been found to be 476 GPa, about 7% greater than diamond. Diamond is a polymorph of
the element carbon. Graphite is another polymorph. The two share the same chemistry, carbon, but have very different structures and properties. Diamond is hard, Graphite is soft (the "lead" of a pencil). Diamond is an excellent electrical insulator, Graphite is a good conductor of electricity. Diamond is the ultimate abrasive, Graphite is a very good lubricant. Diamond is transparent, Graphite is opaque. Diamond crystallizes in the Isometric system and graphite crystallizes in the hexagonal system. Somewhat of a surprise is that at surface temperatures and pressures, Graphite is the stable form of carbon. In fact, all diamonds at or near the surface of the Earth are currently undergoing a transformation into Graphite. This reaction, fortunately, is extremely slow.

Diamonds

Diamond is the ultimate gemstone, having few weaknesses and many strengths. It is well known that Diamond is the hardest substance found in nature, but few people realize that Diamond is four times harder than the next hardest natural mineral, corundum (sapphire and ruby). But even as hard as it is, it is not impervious. Diamond has four directions of cleavage, meaning that if it receives a sharp blow in one of these directions it will cleave, or split. A skilled diamond setter and/or jeweler will prevent any of these directions from being in a position to be struck while mounted in a jewelry piece. As a gemstone, Diamond's single flaw (perfect cleavage) is far outdistanced by the sum of its positive qualities. It has a broad color range, high refraction, high dispersion or fire, very low reactivity to chemicals, rarity, and of course, extreme hardness and durability.

Hardness: Diamond is a perfect "10", defining the top of the hardness
scale, and by absolute measures four times harder than sapphire (which
is #9 on that scale). Clarity: Diamond is transparent over a larger range of wavelengths
(from the ultraviolet into the far infrared) than is any other solid or
liquid substance - nothing else even comes close.Thermal Conductivity: Diamond conducts heat better than anything - five
times better than the second best element, Silver! Melting Point: Diamond has the highest melting point (3820 degrees
Kelvin)Lattice Density: The atoms of Diamond are packed closer together than
are the atoms of any other substance Tensile Strength: Diamond has the highest tensile strength of any
material, at 2.8 gigapascals. However, that does not quite translate
into the strongest rope or cable, as diamond has cleavage planes which
support crack propagation. The strongest ropes can likely be made from
another material, carbon nanotubes, as they should not suffer from the
effects of cracks and break. Still, if a long, thin, perfect crystal of
diamond could be manufactured, it would offer the highest possible
pulling strength (in a straight line - don't try to tie it in a knot!)

Amethyst