Whilst gemstones, regardless of type, can have their physical measurements taken by anyone with a decent set of callipers and scales, it's impossible for someone who isn't an expert to determine the cut, exact colour, and fineness of a stone, or to be able to determine whether any occlusions (internal imperfections) are present or how they will affect value.
The most obvious answer is the demand and supply however one most remember that there are several factors at play here since Gemstones are precious, rare and durable.
Here is a datapoint: To get .5/half carat of a Diamond one has to mine and process approximately 1 tonne of ore. Now this ore is located in jungles, forests, mines etc so you can imagine the costs involved- Human Labour, Fuel, Machinery etc.
Several other factors such as cut, colour, clarity, carat weight etc also affect the price of the gemstones. Add in it powers of negotiation etc and you can see that it is a complex matrix
Colored Gemstones come in a multitude of hues, tones, shades, shapes and that makes it difficult to have a singular definitive price or a gem price index unlike Diamonds where range of color and shapes is very limited
- Rarity and Diversity
Rarity is directly proportional to Gemstone price
There are several factors that determine the price per carat of precious colored gemstones. The prices are directly proportionate to several factors. And also the prices of gemstones do not increase with mathematical progression, rather with geometrical progression.
For example, if a gem, which weighs 1 carat, may cost Rs.35,000 but if all things remain equal the same gem at 2 carats may cost upto Rs.1,40,000 per carat just because a 2 carat Gem would be rarer than a 1 carat Gem. There is no set price range for colored gemstones. The price for the same colored gemstones may vary from as little as Rs.500 per carat upto even Rs.7,00,000 per carat depending upon the quality and several other factors.
And for the classic colored gemstones-The classic Big Three of Colored Gemstones- Rubies, Emeralds and Sapphires the costs increase dramatically as the quality and size of the gem increases. Below are listed some of the factors that determine the cost of colored gemstone.
Gems that are rarer than others command a higher price per carat than the gemstones that are available relatively easier. Gems like Diamonds, Sapphires, and Rubies are more expensive than gems like Garnets, Amethysts or Peridots etc. Having said that it is also important to state that even though Sapphires, Rubies etc are more expensive that than the others it also has to be said that some gemstones are more rare than others, like Rubies are far more rare that Sapphires. Hence a Ruby would be of a higher price than an Amethyst just because Ruby is rarer than an Amethyst.
Taking Rarity to another level let’s take the price among various Rubies. A Burma Ruby would be priced higher than a Thai Ruby. Why? Because it is more rare than the Thai!. Does this finish the rarity story? No not yet. It’s just starting.
Now you know Ruby is more expensive than a Peridot, You also know Burma Ruby is more expensive than a Thai. So what is complicated? Color! A Imperial Pigeon Blood Burma Ruby would command a higher price than a pinkish red Burma Ruby and the story goes on.
Hence all Burma Rubies will not have the same price. This is the reason why you cannot have a Burma Ruby Price List or a Ceylon Sapphire price list or an emerald price list.
Nature makes precious colored Gemstones over million of years and nature’s capacity to replenish fine specimens is limited.
Rarity is the biggest factor that affects Gem pricing and is directly proportional to the Gem Cost.
For example: a Zambian mine would produce an Emerald of a Vivid and rich green color, where as a Colombian Emerald would produce a spring grass green color.
Whatever the shade of color that is native to that region, the purity of color is the one of the most important factor to determine the gemstones prices per carat of a colored gemstone.
- Clarity: How Clarity Affects Gem Pricing.
The clarity of a gemstone is also one of the important factors that determine the price per carat of a colored gemstone. The rate of a gemstone would increase dramatically as the clarity of a colored gemstone increases.
The lesser the visible inclusions the higher the price per carat. Although inclusions that do not hinder the beauty or color of the gemstones are generally acceptable!
And also fine inclusions are proof that the gem is natural and untreated. However there are some gemstones in which fine characteristic inclusions are accepted, like Emeralds and to some extent Rubies. Gemologists refer to these fine inclusions in Emeralds as Jardins.
Note the difference of clarity in the natural emeralds given below.
- Cut/Shape: Symmetry is Directly Proportional to Price.
The cut of a colored gemstone also has significant bearing on the price per carat. Some gemstones are traditionally cut in particular shapes. Like the Emerald has always commanded more price when fashioned as an Emerald cut, and Sapphires are considered more desirable in the oval cuts.
What ever may be the cut, it has to be made sure that the maximum play and penetration of light takes place so as to bring out the brilliance and scintillation of the color of the gemstone.
The more masterfully crafted the gemstone the better the polish and blemish free surface the costlier the gemstone.
Exotic and unusual shapes, like round, Pear etc are priced at a premium as shaping the gems into these shapes leads to more wastage of the raw material/gem roughs.
- Gem Weight and Size and its affect on Gemstone Pricing.
As the weight of the gemstone increases so also the price. If the above given factors are met and a gemstone increases in weight the price per carat of the colored gemstone increases manifold.
As mentioned earlier the price of precious colored gemstone increase with geometrical progression. For example a gem’s price may increase in geometrical progression for weights upto 3-4 carats, but colored gemstones of 4 carats and above are priced at a premium even above the regular geometrical progression, as the availability of colored gemstones at such sizes is extremely rare.
Even gemstones that are calibrated are more expensive as the wastage percentage increases in order to get gems to one size and shape.
Treatment or Lack of Treatment and its effect on Gemstone Pricing!
Colored gemstones that are not treated/ enhanced in any manner so as to increase its color or clarity are gemstones that command premium prices. Treated gems are relatively cheaper are may be accepted in few jewelry markets, but untreated and natural gems always have and will always be a premium.
It has become extremely rare in today’s market to get untreated colored gemstones with good color and clarity levels, so and untreated colored gemstone with good clarity and color command a premium price.
So a heated Blue Sapphire of the same color, cut, carat weight might be cheaper than an Unheated one by 4 times and maybe more expensive than a diffused one by 200 times. Lack of treatment is directly proportional to Gem price.
- Origin and its effect on Gemstone price!
Even though the origin does not often have much bearing on the price of a colored gemstone, the price may shoot up for some gemstones from certain regions. Like a Burma Ruby comes at a huge premium as availability is extremely rare due to several factors.
So also Kashmir Blue Sapphires come at a price out of reach of most of the seekers of colored gems as mining in this region has stopped and also the color Cornflower Blue peculiar to this region has been placed at a premium by gem connoisseurs.
- Supply and availability:
Depending upon the source that the colored gemstone has been purchased from the price per carat may vary drastically. From the Gem Mine to the end customer the gemstone passes through many hands. Starting from the mine owner to the retailer!
As the gemstone passes from hand to hand, the price increases manifold as each person in the chain keeps some profits and by the time it reaches the end consumer it is out of reach of the common man. So depending upon whom you purchase a colored gemstone from the price may vary by upto 250 – 300%.
- gPolitical/ economic Factors-Other Factors that effect Gem Pricing!
Gemstones are mined and sourced from areas that are not exactly Picture perfect. Imagine sourcing Rubies from Madagascar with rats and roaches for company, or going to Burma to search for a Natural ruby and getting the company of mafia, military police, mosquitoes and snakes as a bonus or getting emeralds from Afghanistan or Colombia. There are several other factors like this one that effect gem price. Of course there is no Price for a Human Life.
So keep in mind the above factors and determine that if you are getting a colored gemstone at a price too expensive for your taste, it probably is! A fine colored gemstone is hard to come by, and to get one that satisfies the above criteria is harder still to get. Colored gemstones are miracles of nature and also very rare. They not only give you lasting value but also color up your life!
Contentment is a Pearl of Great Price and whoever procures it at the expense of a ten thousand desires makes a wise and a happy purchase.
We, at MyRatna strive to strike the right ratio of natural characteristics of a Gemstone and preserve the wholeness along with a price range which is friendly to every pocket.