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Rarity
Of the 4 C's, Carat Weight is probably one of the most important considerations with respect to rarity, value, and consumer preference. In fact, Carat Weight, or how much the diamond weighs is the most significant value factor in a diamond. Because diamonds by nature are rare, a 2 carat diamond is actually about 3 times more valuable than a comparable quality 1 carat size. Statistically a 1 carat is one in a million diamonds mined, and a 2 carat is one in five million diamonds mined. Therefore, all things considered a 2 carat diamond is really "value priced" based on the rarity factor.
Pricing
Larger diamonds are much more rare, thus commanding a higher price/per/carat. Carat weight affects the value of a diamond by about 10-20% for each step in size difference. Also, "magic sizes" refer to major carat weight categories, for example exactly 1.00 carat, or larger, and can prompt "price premiums". To calculate the price of a diamond you multiply the carat weight by the price/per/carat. For example: if a 1.25 carat diamond was priced at $10,000 per/carat the diamond would be sold for $12,500.
* http://www.diamonds.com/education/Carat.aspx
The price is way to variable, for example a two carat diamond can be worth 10 tens that of another two carat diamond, and ten 1/10 diamonds are worth less than 1/20 of a one carat diamond of he same grade. the value of a diamond is affected by things like the amount of flaws it has, where the flaws are, the color of it, the cut of it, the florescence in it, its size, and tons of other things.
There is no simple answer for this or a standard one. It is completely dependent on size and quality. A set quality diamond will increase in price per carat as it's size increases. All four c's affect the price per carat so you would have to have a specific in each category to even try to find a price per carat, example you are looking for a 1 carat, G color, VS1 clarity, well cut diamond.
That depends on the cut, carat, color and clarity. For e.g, a round 1 carat D color, IF clarity, and an excellent cut diamond costs about $11, 081 and a 1 carat marquise diamond with the same characteristics costs about $17, 066, both of which are GIA certified. Another example is of a round G color, VS1 clarity, very good cut diamond is for $5521 and a princess diamond with the same characteristics is for $4391. So it all depends on what you are looking for and what your budget is.
I think that depends on the size and clarity and shape of the diamond.
A one carat diamond ring is £624.00 .
Black diamonds can be estimated approx. $10,000 per carat.
The average price of Russia's exported diamonds makes up $22 per carat you will get less selling in the country since they mine them there.
"The market value for natural blue diamonds is very high. They are very rare and highly sought. The average price for a one carat blue diamond may be as high as $150,000."
Every diamond is valued by its carat weight, its colour, its cut and its clarity. There is no standard. Without endorsement, you can price black diamonds, below.
A carat of diamonds is worth whatever someone will pay you for the carat.
Red Diamonds are approximately USD $2-2.5 million/carat. Just like regular diamonds, the price may vary by clarity of the actual stone.
The price for a one carat diamond cluster will vary greatly depending on things such as the quality and size of the diamonds in the cluster. The type of ring setting is also a factor in price such as 10, 14, 18 or 24 carat gold. An example is a 10k white gold diamond cluster is $600 at Zales but a 14 carat diamond cluster on the Ross Simons site sells for $2,471.
Visit a local jeweler to price diamonds of this carat weight, and you'll pay for it depending on its cut, clarity and colour.
Carat is the unit of measurement used to measure diamonds, other gemstones and pearls.
Three carat diamonds weigh three carats: that's how 'big' they are.
The value of a diamond, regardless of the year, is based on its cut, carat weight, colour and clarity.
Diamonds are measured in carats, the bigger the stone the larger the carat. If you had a 2 carat diamond it would be worth thousands. My rings are only 0.25 carat which is small