We love diamonds

Learn more about the king of all precious stones

Excellent quality

A single ray of light is all that is needed to unleash the fire within. Each stone is special, born in the depths of the earth.

The quality and thus the value of a diamond is determined by the combination of the so-called 4 Cs - Cut, Color, Clarity and Carat.

At acredo we only offer very good quality diamonds. Starting from a stone size of 0.3ct, every stone comes with a certificate from a renowned international testing institute. The cut of the best diamonds is always excellent and shows Hearts & Arrows.

International top certificates

International top certificates

Not all certificates are equal. For your security, we only have certificates from the three leading institutes, GIA, IGI and HRD, in our portfolio. These are independent international testing institutes that have an excellent reputation due to their particularly strict standards.

Once the tests have been undertaken by several experts, the authenticity and quality of the diamonds are recorded in a certificate. The certificate is your diamond’s ID card.

The institutes’ assessments take place according to internationally agreed and accepted criteria.


The 4Cs were developed by the Gemological Institue of America (GIA), which was founded in 1931 and prides itself for being unbiased and reliable.

IGI, the International Gemological Institute has been specialised in analysing and certifying diamonds, precious stones and jewelry since 1975. IGI laboratories and registered offices can be found at diamond hotspots across the globe.

HRD stands for Hoge Raad voor Diamant. This institute is based in Antwerp. A double-coding system guarantees the objectivity of appraisals by HRD.

 The sign of love: Hearts & Arrows

The sign of love: Hearts & Arrows

At acredo, all diamonds from 0.3ct not only have an international expertise, the best also show Hearts & Arrows.

The sign of love can be seen with a special magnifying lens in this special diamond cut form: eight arrows on the top side of the diamond and eight hearts on the bottom side.

Only around 1% of cut diamonds have this degree of perfection because it requires very special angle and length ratios. This is the only way to achieve absolute symmetry.

Brilliant-cut diamonds with Hearts & Arrows excel with an outstanding sparkle. Rare treasures from the depths of the earth.

 The sign of love: Hearts & Arrows


The weight of a diamond is specified in carat. One carat weighs 0.2 grams. The term carat stems from the seeds of the carob tree, which weigh 0.2 grams.

This weight unit has been used to measure diamonds across the world since 1875. The higher the number of carats, the higher the price of a diamond.

In addition to the weight, the size of a diamond is subject to other factors such as the cut, the shape of the stone and the proportions.

The visual size of a stone is also influenced by the length of the finger and the setting. White precious metal settings such as white gold and platinum increase the visual size of the stone.



Color describes the color of the diamond. The less color a diamond has, the more valuable it is.

The colorless or white diamonds are graded together with pale yellow diamonds. The rare colors like rose, red, blue, green, yellow, brown and black are graded separately. Some of these “fancy diamonds” are even more valuable than white diamonds.

According to GIA standards, the color scale ranges from D to Z. D is totally colorless and extremely rare.

Diamond color is graded by a gemologist using master stones. An untrained human eye has difficulties differentiating up to H. As from I, the stones gain hue.



Clarity describes the purity of the diamond. This criterion separates rare pure diamonds from diamonds with inclusions.

Inclusions can be, for example, crystals or impurities. The impurities could be traces of other minerals or foreign substances. There could be also natural fissures or growth phenomena. The inclusions are graded by number, size, location and type. The scale reaches from large, easy to see inclusions (I3) to flawless (FL/IF).

Flawless diamonds have no visible inclusions under 10x magnification.



Cut describes the cut of the diamond. The brilliance of a stone is determined by the cut and the proportions of the stone. The cut is thus one of the fundamental assessment criteria of a diamond.

Cut grading ranges from fair, good and very good to excellent for outstanding brilliance with the best proportions and symmetry. In terms of proportion, the angle and 8 other criteria are tested, and with regard to symmetry, 18 parameters are reviewed.

As the stone’s brilliance is very important to us, we at acredo concentrate exclusively on very good to excellent cut diamonds.

Choice of cut

The most well-known and well-loved cut is the round brilliant-cut with its maximum 58 facets. The light reflections that give the diamond its fascinating sparkle arise when these facets are at a perfect angle.

Other well-loved diamond cuts include the four-sided princess cut, the rectangular baguette cut and the emerald cut.

Heart-shape is an idea for romantics. But also the navette or marquise cut, the oval or pear shaped cuts have their own special allure.

Choice of cut


A diamond has fluorescence if the element Boron is present when a diamond is formed. The strength of the fluorescence is stated in certificates in terms of none, low, medium, strong and very strong.

Fluorescence is understood to be the spontaneous emission of light shortly after the material is exposed to a high-energy light source, e.g. UV light or daylight.

Low to medium fluorescent diamonds have a slightly blue shimmer.
Strong fluorescent diamonds can appear cloudy or milky.

However, in most cases fluorescence doesn’t affect the beauty of the diamond. These diamonds appeal in their own right. Fluorescence lowers the price.


Colored diamonds

You will find colored diamonds at acredo, allowing you to create charming rings and pieces of jewelry. These diamonds are not fancy diamonds but diamonds with changed color.

The color of the diamond is changed with pressure and heat. This process imitates the natural process during which fancy diamonds develop their color.

In this process, each diamond is examined for existing supporting elements that allow light dispersion before undergoing one or more HTHP processes.

Various blues, a warm gold or cognac color, a fresh green, red and black are available for your exclusive creations.

Value performance of diamonds

Value performance of diamonds

Diamonds concentrate a very high value in a very small space. The price performance of diamonds is relatively stable. Other assets such as gold or stocks are subject to higher volatility. The price of diamonds has been on a steady increase for over 30 years. The diamond market was only marked by more material price fluctuations between 2008 and 2011. Price performance can depend on the size of the stones. The price of larger stones increases at a slower pace. As the annual demand for diamonds continues to increase and the primary and secondary deposits become depleted, experts expect to see prices rise in coming years.acredo brings you diamonds at an excellent price-quality ratio. Let our specialists advise you.

Diamonds as an investment

acredo primarily sees a diamond as a piece of jewelry. We love the beauty and radiance of these unparalleled stones.If you want to combine investment and beauty, we recommend you invest in the highest stone quality. The size of the stone depends on your budget.A certificate proving the quality of the stone is important for an investment diamond. At acredo you automatically receive an international top certificate from GIA, IGI or HRD for every diamond from 0.3 ct.Invest in the color, clarity and, most importantly, the cut. The importance of the cut is growing as this is decisive for the reflection of the incoming light and thus the vibrancy of the stone.Therefore, we at acredo only stock diamonds 3x excellent cut.Our recommendation for an investment stone is thus: river flawless with 3 x excellent and Hearts & Arrows. You will be thrilled.


The Diamond: king of all precious stones

It is rare, it is made of resistant material, it sparkles in all directions: the diamond is derived from the Greek word "adamas" (invincible). It is not surprising that it is referred to as the king of all precious stones. And as the king, it has even more to offer: it reflects up to 100% of the incoming light and therefore has the highest refractive index of all precious stones with a value of 2.42. The diamond is one of the hardest known minerals in the world and scores 10 on the Mohs scale of mineral hardness. Diamonds are rare and very difficult to obtain because they are formed under great pressure at a high temperature of 1700°C and at a depth of 150 to 200 kilometres. Today, great efforts are needed to extract diamonds both from open-pit mines and underground mines as well as from offshore mines. Only a quarter of these natural treasures are suitable for use in jewelry. Therefore, diamonds are a precious token of love.

The 4 Cs: determining the quality of a diamond

Carat, clarity, color and cut are the so-called four Cs, used to judge the quality of diamonds. The expression carat is named after the seeds of the carob tree due to their weight (200 milligrammes) and has been used to weigh diamonds across the world since 1875. The price of a diamond depends very much on its clarity. The fewer inclusions a diamond has, such as crystalline structures or other minerals, the higher the classification and the more expensive it is.

If no inclusions are visible in the diamond under tenfold magnification, the diamond is classed as flawless and is regarded to be particularly valuable.

The color also determines the price of a diamond. Colorless diamonds are very popular and expensive, especially in the world of jewelry. However, fancy diamonds in colors like red, blue and black are also very valuable due to their rarity.

In contrast to the first three components, the cut of the diamond is influenced by the specialists. The cut as well as the proportions determine the brilliance of a diamond. Diamonds can be cut with the round brilliant cut, the square princess cut or the rectangular baguette cut, in a heart shape, oval, marquise, or pear shape.

International top certificates at acredo

You will receive a top international expertise for each diamond from 0.3ct purchased at acredo. For your security, we only use certificates from the independent, international institutes GIA, IGI and HRD. In addition to the dimensions of the diamonds, these certificates include the criteria shape, weight, color, clarity, polish, symmetry, proportion, and fluorescence. Each diamond is as unique as your love and has therefore been assessed and classified by several specialists according to different hard criteria.