About Us

About Us
ronny When I turned 16, I started to be trained by qualified diamond cutters to bring out the beauty of a rough diamond.

After years gaining experience and having learned to cut all the different shapes, I was invited along with 2 other cutters to run a factory in the South of Spain.

After expanding the factory, 10 years later, I was asked to oversee a production line in India.

Being in this sector for many years, I came to realize that more and more people started to sell and buy pre-owned jewellery online, as this was a better deal for both the seller and buyer. However when it comes to jewellery not only is expertise important, but also the trust factor. We all want to receive what we pay for. Therefore with more than 30 years of experience in the diamond industry, working in Belgium, India and Spain, I offer my professional knowledge to both the buyer and seller.

ronnyWhen jewellery is sent to De Winter Diamond, we use our expertise to authenticate the item and check the 4 C´s: Carat, Colour, Clarity and Cut.

Our aim is to get the best price for the seller and to make sure the buyer gets the quality they paid for, so they can enjoy the beautiful jewellery the fell in love with for years to come.

Diamond Education


What are the 4 C´s of Diamonds and What Do They Mean?


Carat is a metric unit equal to 0.20 grams, and is used as the standard unit weight of diamonds.

For diamonds, prices are expressed per carat. The carat weight has the biggest impact on the price of a diamond.

In the diamond trade, size is less important than the quality of the diamond; consumers however, tend to prefer larger diamonds because of their higher status.




The colour of a diamond has the second biggest impact on its price, after carat weight.

Though many diamonds appear colourless, most have at least a trace of yellow or brown colour.

Diamond experts grade these “colourless” diamonds by deciding how closely a stone approaches colourlessness. 

Diamonds in colour such as blue, pink, purple or red are referred to as fancy colour diamonds and are incredibly beautiful but more expensive due to their rarity.




Clarity describes the absence of internal and external flaws. A perfect stone with perfect clarity is rare, although some flaws cannot be seen without using magnification. 

The clarity of a diamond is understood in grades:

* FL - Flawless

   These stones have no imperfections inside or on the outside under a loupe of 10X magnification 

* IF - Internally Flawless

   This grade is given to diamonds with no internal flaws and only minor external blemishes.

* VVS1, VVS2 - Very Very Slight Imperfections

These stones have very, very small inclusions which are extremely difficult to see under a loupe of 10X magnification.

* VS1, VS2 - Very Slight Imperfections

 These stones have very small inclusions, or imperfections, which are slightly difficult to see under a loupe of 10X magnification.

* SI1, SI2 - Slightly Imperfect

These stones have inclusions, which are fairly easy to see with a 10X   magnification, and can be seen with the naked eye.

* I1, I2 and I3 – Imperfect

These stones have inclusions ranging from moderately visible to very easily seen to the naked eye.




The cut of a diamond refers to the way the diamond was faceted to allow light to reflect from it.

In a well cut diamond, light enters the diamond and reflects straight back to the viewer’s eye.

The width and depth can have an effect on how the light travels within the diamond, and how it exits in the form of brilliance.

Diamond cutters will occasionally sacrifice the ideal cut to create the largest possible diamond, making a deeper cut or more shallow, to allow the light to reflect as well as possible.

If the cut is too shallow, the light is lost out of the bottom, causing the diamond to lose brilliance.

Contrarily, if the cut is too deep, light escapes out of the sides of the diamond, causing a dark appearance.

Polish and symmetry are also two important aspects of the cutting process.

The polish grade describes the smoothness of the diamond’s facets, while the symmetry grade refers to the alignments of these facets.

For the most beautiful diamond, look for a symmetry grade of excellence (EX) very good (VG), or good (G). 

Avoid diamonds with symmetry grades of fair (F) or poor (P).