Skip to main content

Carat

Diamonds have weight and they are measured in terms of carat(cts). Diamonds can also be measured in grams or kilogram but carat is the term used because of the history related to it.

History:
    All seeds of carob tree weigh the same. Each seed weigh 200 milligram (mg) exactly and they are used as standard to measure the weight of gemstones and pearls because there were no machines in the past. They called each seed weight as a carat which is 200mg and carat term is very widely used for measuring the weight of diamonds.
    1cts       = 200mg
    5cts       = 1g
    100cts   = 20g
    3106cts = 621.2g world's largest diamond ever recorded. So now you understand that single diamond do not come in kgs.

Carat and its importance:
    Among the 4c's of diamond, the value is highly dependent on carat. The bigger the weight- the higher the price. They start from 0.01, 0.02, 0.03, 0.04, ......., 0.61, 0.62, ........, 0.99, 1.00, 1.01, ........, 1.99, 2.00, 2.01, ......., etc. If the diamond price of 0.37cts is $1670 then similarly 0.38cts is $1700 and 0.39 is $1730. A difference of $30 for every 0.01cts more weight.
    Diamonds also have size ranges. Example 0.30 to 0.39 is a size range and 0.40-0.49 is next size range. Lets say diamond weighs 0.40cts and its price will no more be $30 more than 0.39cts. It can be $90 more than 0.39cts because it falls in the next size range. If you observe the price difference between 0.39cts and 0.40cts is $90 for 0.01cts. This is how it works. If the diamond falls in the next size range then the diamond price increases multiple times. You can never increase weight of diamond but you can only save the weight in manufacturing. 0.40cts is a break size which is start of a new size range. Once you hit the break size or next size range the price value of diamond jumps multiple times.
    Almost all diamond industry follow rapaport for diamond rough valuation and polish price. Rapaport have all size ranges and weights starting form 0.01 to 10.00cts+. Above 10.00cts is considered as special diamonds. Lets see how we can use the rapaport to calculate the price of diamond

What happens if we overpolish the diamond in manufacturing?
Example 1: Diamond estimated for 1.02cts H VS2 EX at $5431. The diamond moved into manufacturing and the polisher by mistake polish too much more on the facet and the diamond end up as 1.01 H VS2 EX at $5378. Loss here is $53
Example 2: Diamond estimated for 1.02cts H VS2 EX at $5431. The diamond moved into manufacturing and the polisher by mistake polish too much more on the facet and the diamond end up as 1.00 H VS2 EX at $5325. Loss here is $106
Example 3: Diamond estimated for 1.02cts H VS2 EX at $5431. The diamond moved into manufacturing and the polisher by mistake polish too much more on the facet and the diamond end up as 0.99 H VS2 EX at $4009. Loss here is $1422

    Also check the value loss of diamond if there is drop in color, clarity, cut and fluorescence and compare with carat when you loose a break size. Then you will observe loosing break size is a huge damage. No manufacturer will ever want to loose break sizes.

How to measure weight of diamonds?
    Today we have many weighing scales available in the market- Mettler scale, sartorius, etc. They can measure upto 4 digits after decimal.

Comments

Post a Comment

Popular posts from this blog

Cut

Diamonds are luxury goods. People are willing to buy them irrespective of high price because it is best suitable for jewelry. Why are diamonds on high demand for jewelry?     Diamonds sparkle better than any other jewelry today. They store light and sparkle. Today it is a luxurious status of having diamonds as necklace, bracelet, rings, etc. Cut plays a vital role in diamonds fire, brilliance and scintillation which we will discuss further. Cut is general terms means craft. Like any other material wood, limestone, etc; diamonds are also crafted. History:     Diamond cutting process has been known since 6th century in Indian subcontinent. In 14th century, diamonds were fashioned for jewelry.  Before 15th century it was cutting natural diamonds with other natural diamonds only. Slowly improvements were made and in 15th  century a tool called scaif was introduced by a Flemish polisher called Lodewyk Van Berquem. This tool is infused with diamond dust and olive...
3 comments
Read more

Clarity

     Diamonds are formed with carbon and few other elements(nitrogen, boron, etc) along with some air, dust, packed inside it. These packed particles are called inclusions. They define the clarity (grade) of the diamond. In simple words, diamonds clarity grade depends on inclusion location, number of inclusions, inclusion color, inclusion shape and reflection. All these factors are considered under 10X magnification and a final grade is decided by the quality checker from the top view. Grades are as below: IF- Internally flawless VVS1- Very very small included 1 VVS2- Very very small included 2 VS1- Very small included 1 VS2- Very small included 2 SI1- Small included 1 SI2- Small included 2 I1- Included 1 I2- Included 2 I3- Included 3     Was it difficult to find the difference between IF, VVS1 and VVS2 clarities? This is how difficult it is to grade the diamonds in these higher grades. So quality checkers will use higher magnification upto 20X or more to find t...
Post a Comment
Read more

Diamond Basic Knowledge

Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. This carbon is a pure carbon. Carbon is not only the chemical element in diamonds but diamonds can also have nitrogen, boron, etc in their bond structure      Diamond has the highest hardness and thermal conductivity of any natural material, properties that are utilized in major industrial applications such as cutting and polishing tools. People often get confused between hardness and strength. Hardness is resistance to scratching or indentation whereas strength is to withstand force. Diamond is hard but not strong. It is impossible to scratch the diamond with any other substance except diamond which is basically hardness. It is easy to break the diamond with many substances which is basically low strength. Thermal conductivity is a measure of its ability to conduct heat. Due to stiff chemical bonds between light carbon atoms, diamond has an incredibly high t...
Post a Comment
Read more
☌