Take good care of yourself. You are a GEM!


March 10, 2015

Before buy loose gemstones online, it's necesary to know these concepts:




 A GEM IS A NATURAL PRODUCT with some specific characteristics:

BEAUTY. It’s a personal concept. If the gem is beautiful for you and makes you feel beauty, then, that’s your gem.

Beauty is related with the visual sensation: color, brightness, clarity….

RARITY. A gem is a nature miracle. Depending on its exclusivity this will be its price.

DURABILITY. It has to be transmitible, inheritable. Consequently it is very important the hardness, the exfoliation and the resistance to certain processes or products.




Rarity means exclusivity. If you want to buy loose gemstones online, and if you want to own a gem that few people have, you will have to pay for it.

Rarity is about the amount of this gem in market either by the low production of it in the nature or else by the difficulty in extraction and handling.




Air contains particles of silica, with Mohs scale hardness 7.

Any stone with lower hardness than 7 is subject, over time, to become scratched on surface or chipped in the edges. As a result of this its brightness will be reduced. In this case you’ll have to provide an special treatment.




The convenience of one gem or another will depend on the use there of and how often is going to be worn.

Before buy loose gemstones online, you need to be conscious of the damage a gem suffers due to the daily use.

Earrings don’t suffer the same as rings do. A special-ocasion gem doesn’t suffer the same as an every-day sleeping-with gem.

You have to consider the weight of earrings with big gems.




Is a gemstone a good investment? Yes and No

If you buy a sealed diamond with a highly prestigious certificate, you keep it for years and after that you sell it, you will probably earn money.

If you buy a diamond, with certificate, you set it in a ring, you use it for years and after that, you try to sell it, probably, you won’t recover your money. And probably the stone will be scratch or chipped.

Other cases are for example an iconic high valued jewel with outstanding characteristics that make it a unique item. Or jewels made for prestigious goldsmiths. In these cases, benefits could be enormous but initial investment is important




C1           CARAT.  Its weight 1ct=1/5 grams

C2           COLOR .  If we talk about a colorless diamond, the more colorless the more value and price. In this case, yellow  color is penalized

 If we talk about colored stones, the more vivid color the more expensive

C3           CLARITY.   Gems are nature-made and in this process they’re not alone. Their companions could get trapped in their crystalline net. The massive presence of these “intruders”, that we call INCLUSIONS, could penalized their price

C4           CUT.  Talking about cut is talking about equilibrium, quality of work … an excellent cut means exquisite work that supposes proportions, accuracy in the facets, finishing polished,….




IT’S VERY EASY, the heavier the more price. Of course if the quality is the same!

Weight of gems is named in CARATS, which has no relation with carats of gold.

A two-carats stone doesn’t cost twice one-carat stone. Prices increase exponentially.

Let’s see the units of measure:


                                      1ct(carat) = 1/5 grams= 0.2 grams

                                      POINT= 1/100 ct (for small diamonds)

                                      MOMME= 18.75 ct = 3.75 grams (for pearls)




The concept is quite complex because is a mixture of several things and is crucial to determinate the commercial value of a gemstone.

Once you’ve chosen a gem, you ‘ll realize that not all her sisters are identical.

Color in Burma saphires have no rivalry but among them, there are some of them with a higher color intensity than others.

 You have to watch gems with different types of light. After watching it under the shop desk light, go outside and watch it again. You will get surprised!




Natural origin of gems reminds us that, in the formation process, gems are not alone. The geological process means presence of other actors (foreign bodies, small crystals, mineral fluids,….)

Sometimes the presence of inclusions make gems look even nicer. It happens with silks (rutile inclusions) in ruby. But sometimes these inclusions play down transparency and beauty with no extra-benefit.

Colorless diamons ( we don’t talk about fancies) are very penalized if inclusions are visible at first sight.

Colored gems are different, as some of them use to have inclusions, for example, emerald or rubellite tourmaline.


10. CUT


In the past, gems were worn in rough. After some time, lapidaries started to polish their natural faces, which increased the brightness. Cabouchons were very common.

Since XVI century we can find faceted gems. It stands out the beauty of a mineral or material

Quality in cut affects in gem beauty. Deep pavilion makes a loss in the brightness and you can get what we called “fish eyed”.





Why when you buy a car you get its papers o when you buy a bag you get its composition but when you buy a gem you get nothing?

That’s enough!

When you buy a gem you have to ask for the proof that what you have paid for exactly what you have. You’re not supposed to be a gemologist!

A gemologist will not certificate a piece of glass or a plastic bean. But, we insist, if the gem has important price, it has to be accompanied with its certificate of authenticity.




As a famous cinema-star, gems have imitators. They are stones from different origins (natural, artificial or synthetic) that can replace a high value gem, but their composition is completely different.

For example, a red piece of glass could imitate a ruby or a green tourmaline could imitate an emerald

Imitation always means cheating, means trying to be something that is not  because of higher value




Who has not heard about cubic zirconia, famous in the 80’s for replacing diamonds?

Cubic zirconia is a very close and clear example of artificial gems. They are man-made but there is no equivalent in natural. It means different characteristics and consequently will be, initially, easy to distinguish from the gem that are supposed to be.




Synthetic gems are man-made with the same composition and physical characteristics than the natural gem

Then a synthetic ruby has the same composition than a natural ruby, same hardness, identical refraction index…

In a synthetic gem you can see all the efforts that companies in the sector make in order to get inclusions as similar as natural

Companies with business in synthesis make big efforts to get inclusions looking as natural as possible.

Dr. Joaquim Nogués, head of gemology department in Barcelona University (UB) used to say:  “Don’t forget that international community has spent millions and millions of dollars making a synthetic diamond, but diamond”




Man is treating gems from centuries and the improving day at day. Gemstones are treated to improve clarity, color, hardness… 

For instance emeralds are usually treated. Everyone knows it and accepts it due to the presence of fractures and fissures in the stone that are refilled to get a nicer gem.

But depending on the refilling , the emerald will have different value.

Usually colorless oil is used to get a more vivid gem with high price

But sometimes they use a green colored oil to increase the green color. Instead of a pale green colored and very fractured emerald you get an attractive green colored but its value will be very low.




 “There is no such thing as a free lunch” used to say my mother. And it’s true

You have to ask for the gem “label”. Gems have to be sold with their certificates where you could see exactly what are you buying

When you buy a jewel, bracelet, ring or collar, with diamonds doesn’t matter big or tiny, you should insist of getting a document explaining what are you buying and it has to be included in the price!

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