Technical Informations

AVAILABLE QUANTITIES

All gemstones displayed are unique; it is possible to order a single unit or a pair as per item description. All items are immediately available on site, except those indicated as “SOLD”, these
are no longer available as they have been recently purchased online and automatically placed in this status by the system.

CERTIFICATION

We guarantee that all our gemstones are natural. Every gemstone is analyzed by our gemmologists before being put on sale.
Where not included in the price, the issue of the gemological certificate is optional. Our certificates comply with the UNI directives on gemological analysis. The document reports all the physical characteristics of the gem and is signed at the bottom by the supervisor, the laboratory manager.

DIMENSIONS AND WEIGHT

Gemstones sizes are expressed in millimeters up to one hundredth of a millimeter.
Real sizes of gemstones and jewels can be easily deducted comparing the sizes shown in the detailed product description to the dimensions of a coin or using squared paper or a millimeter ruler.
Gemstones weight is expressed in carats (ct.) 1 Carat = 0.2 grams
Gemstones of same carat weight can have different sizes due to their specific weight, shape and cut.

Natural gemstones often have crystal inclusions, cleavage, feathers, cavities, etc. All these flaws are usually classified under the generic term of “inclusions”.
Internal inclusions are analyzed in order to establish the clarity of a gemstone. Diamonds clarity grading system is different from colored gemstones one.
The definition of clarity has no meaning for non-transparent gems.

DIAMOND CLARITY SCALE:
International regulations on diamond clarity definition require inclusions to be identified using an achromatic aplanatic 10x loupe.

CLARITY

CLARITY SCALE OF COLORED GEMSTONES:
For the determination of the clarity of colored stones, the GIA directives provide that the identification of inclusions is carried out by naked eye with correct eyesight.

Colored gemstones belong to different mineral species with different clarity ranges that can be grouped, accordingly to GIA, into three types:

Type I: Gemstones that are commonly pure, with no inclusions visible to the naked eye. It includes: aquamarine, pink or yellow beryl, green tourmaline, blue zircon and tanzanite.

Type II: Gemstones with minor inclusions that do not detract from their beauty. It includes: alexandrite, peridot, garnet, iolite, spinel, quartz, zircon, corundum (excluding ruby) and all the tourmalines (excluding green tourmaline).

Type III: gemstones that always have inclusions due to their geological genesis It includes: emerald, red beryl, ruby.
Gemstone clarity is evaluated considering the detrimental effect an inclusion can have on transmitted light and thus on transparency and brilliance of the gemstone itself.
Please note: the detrimental effect of an inclusion is lower in Type III than in Type I. In other words, the inclusions in Type III gemstones, which derive from their genesis or due to the rarity of the material, are commonly accepted, while inclusions in Type I gemstones, which often lack them, can reduce their quality.

TRANSPARENCY

The definition of clarity has no meaning for non-transparent gemstones.
For commonly non-transparent gems such as Opal, a TRANSPARENCY scale is used.
The level of transparency is defined according to the following criterion:

COLOR

The definition of color has different parameters and different quality gradings for diamonds and for other gemstones.

DIAMOND:
An alphabetical grading-scale that describes the exact hue of yellow in the gemstone is used for diamond color grading. The scale goes from D, representing colorless diamonds, to Z, representing yellow diamonds.
It is necessary to point out that nature occasionally produces diamonds with yellow, red, blue, brown and even black hues.
These are the so-called fancy diamonds.

FLUORESCENCE:
Diamonds when exposed to ultraviolet light can emit a glowing light. This is the typical property of certain materials that emit visible light if exposed to ultraviolet rays.
The possible ratings of fluorescence can be: None – Very slight – Slight– Distinct – Strong.

DIAMOND COLOR GRADING SCALE:

COLORED GEMSTONES:
The color grading for gemstones other than diamonds is expressed by GIA grading scale using terms of comparison and hue, tone and color saturation description.
A further descriptive element is the chromatic balancing and covering of the gemstones. Gemstones can often show many hues within the same crystal (Multicolor). Uncommon colors for a gemstone are called fancy colors.

CUT

Gemstones cut is defined through the following criteria.
SHAPE: round, oval, pear, square etc.
TYPE: brilliant or step-cut, rose, mixed etc.

Cut samples:

The cut quality plays an important role for establishing the value of a gemstone as it can enhance the color and the brilliance of a gemstone. The cut quality is evaluated using the following criteria:
Proportions
Symmetry
Polish
The best evaluation of these parameters is an indication for a precise cut and greatly affects the brilliance of the gemstone.

BRIALLANCE:
The overall evaluation parameter for cut is brilliance as it represents the interaction of all the aspects described above (proportions, symmetry, polish). Brilliance is the quantity of light that
can be transmitted to the viewer’s eye by a gemstone.
The light transmitted by a gemstone is the result of the refraction and internal reflection of the light rays that facets bend and refract back to the crown.
An ideal cut allows the total internal reflection and the best light transmission through the crown. The definition of ideal cut can only be found in diamonds reports.

ORIGIN

The word natural specifies the very origin of the gems, excluding laboratory products or synthetics that are not part of our supply.
Then we indicate the geographical area of extraction / import of the gemstone. NB: In the gemological certificate the geographical origin cannot be shown for lack of specific physical evidences and matches into the gem. The Gemologist analyst normally is not aware of the import area of the gemstone but can trace its geographic origin only according to the study of typical inclusions inside the crystal. In case the evidences are sufficient the origin of the gemstone will be indicated in the following way.
Es Colombian emerald, “Origin: Evidences suggest Colombia.”
If the crystal is very pure the evidences may not be sufficient for this type of deductions.

GEMMOLOGIST’S NOTES

In this field we report any comment of the gemmologist following the gem analysis.
We also specify the widespread and commonly accepted treatments as the thermal heating of corundum (rubies, sapphires) or oiling for emeralds.

EVALUATION

Our expert gemmologists personally evaluate important parameters such as color, clarity and brilliance of the gemstone. They grade every gemstone from 1 to 10, as shown in the detailed gemstone description with the corresponding number of green stars, so to help you understand the quality of a gemstone.

QUALITATIVE COLOR GRADING:
Qualitatively, the gemstones with higher Saturation (color intensity), medium Hue (light or dark color) and more typical or rarest Hue for the mineralogical species in question, are more valued.

QUALITATIVE BRIALLANCE GRADING:
The qualitative evaluation of brilliance is proportional to the amount of light that the gem is able to return to the observer’s eye. The brilliance depends on the cut and transparency of the crystal.

QUALITATIVE CLARITY GRADING:
Each gemstone in our catalog is evaluated in relation to its mineralogical species, type of belonging (TYPE I, II, III) and the detractive power of the inclusions with respect to the specimen presented (the evaluation is performed by a professional gemologist).