The five valuation factors

The five valuation factors

Five factors (size, shape, color, flaming or luster, surface) are used to determine the quality of each pearl.

The Conch pearl is one of the few natural pearls that show a flame structure due to its nature. This is generally an indication of their peculiarity. In their classification the flaming is evaluated instead of the luster therefore.

Two pearls with the same factors (e.g. identical carat weight) can vary significantly in value due to different conditions in terms of color, shape, flaming and surface. Bigger does not mean more valuable. Therefore, all valuation factors must always be considered and evaluated in detail in order to determine the final value.

These are internationally applied valuation factors that have had their significance unchanged since ancient times.


Discover the variety of sizes of conch pearls


Each conch pearl has its own shape


Colorful beauty of conch pearls

Flame Structure

Discover the flaming of the conch pearls


structure of conch pearls

Size (Weight)

The weight and thus also the size of the conch pearls is measured in carats. 1 carat corresponds to 0.20 grams.

The term carat is derived from a natural unit, the seed of the carob tree. A measure with historical background: it was previously assumed that every seed of this tree had the same weight. They have an average weight of 0.20 grams, which actually varies only slightly among the seeds.

The weight/size factor is the only weighting factor that is 100% measurable and can be expressed in exact numbers.

How the price per carat is then calculated naturally also depends on the other valuation factors. The occurrence or rarity plays a major role in assessing the value with regard to size.

For Conch pearls can be remarked: The most common sizes found are 2 to 6 carats, 8 to 12 carats are rare, 20 carats and larger are absolute exceptions and therefore achieve top prices. Hazelnut-sized pearls can weigh more than 40 carats. But these are real treasures, not to say wonders of nature. Those who own it are lucky to have such a special and valuable natural rarity.

ca. ø mm ca. ct
ø ca. 4 mm ca. 0,5 ct
ø ca. 5 mm ca. 1,0 ct
ø ca. 6 mm ca. 2,0 ct
ø ca. 8 mm ca. 4,0 ct
ø ca. 10 mm ca. 8,0 ct
ø ca. 12 mm ca. 12,0 ct
ø ca. 14 mm ca. 15,0 ct
ø ca. 18 mm ca. 35,0 ct
40,4 x 29,6 x 17,0 mm 125,12 ct One of the largest conch pearls ever found in the world


Nonround / Semiround
Symmetrical Oval
Asymmetrical oval
Oblong Oval
Pointed Oval
Drop / Pear Shape

Rating Scale

The perfectly round conch pearl

At the top of the rating scale is the perfectly round conch pearl. However, it is extremely rare. They are also almost never uniformly round, even rounded shapes only occur occasionally.

Symmetrical oval as the
perfect shape

Since round pearls are almost non-existent, a symmetrical oval is considered the perfect shape in second place.

Drop or pear shape,
turnip and triangle

Symmetrical forms such as the drop or pear shape, turnip and triangle follow on the rating scale.

In terms of value, the so-called bouton and lens shapes (button) follow the symmetrical forms. These are flattened round shapes. They are divided into high and low bouton.

Baroque Forms

At the bottom end of the rating scale are the baroque pearls. This includes all pearls with irregular shapes. The term baroque, which originated in the 16th century, is derived from the Portuguese word “barocco”, which means “strange”.

Pearls that come into contact with the shell grow firmly on it. They are called blister or shell pearls. There are pearls recognizing the stalk-like attachment points of the beginning growing together. Narrow, elongated, baroque forms are also called dog’s tooth pearls.


The colors of the Conch pearls correspond to the shell colors of the Strombus Gigas snail.

The dyes are caused by organic substances. The pink color, for example, results from an organic pigment belonging to the carotene family.

The range of colors includes many tones which, 
according to lovers,
reflect all the colors of
the sunset.

They range from white, cream and beige to dark brown, from salmon, apricot and light pink to the beautiful and coveted pink in a wide variety of shades. Brownish-yellow tones are also referred to golden. The color lavender appear only very rarely.

Pearls in color gradients are also possible, e.g. from white to pink.

In the rating scale, a strong pink with a violet hue is given the highest value. It is followed by a strong salmon tone in the line.

This coveted pink coloring can be of low intensity and thus convey the impression of soft pink. It can also be strong and go up to a beautifully bright pink.

The origin of the name “The Pink Pearl” can be found here.

Flame Structure

The special distinguishing feature to other pearls is the so-called flaming, which appears under the smooth porcelain-like surface and ranges from fine silk, silky or velvety, finely flamed to strongly flamed.

Most Conch pearls show this characteristic flame structure, which is an important value and quality feature. The evaluation of the pearl is about the characteristics and structure of the flaming. This in turn depends on the size and growth time of the aragonite crystals or fibers below the surface. A rough structure suggests faster growth as assumed.

Pearls with a surface reminiscent of wet silk are at the top of the rating scale.

In addition to a good eye or magnifying glass, assessing this evaluation criterion requires a great deal of experience and expertise.


Silky intensive flame structure with horizontal pattern
Fiery intense flame structure without uniform pattern
Cloud-like structure
Chatoyancy – Cat’s Eye Effect
Fine silk / velvety flame structure
Light flame structure


A flawless surface is as rare as a perfectly round shape.

Most Conch pearls reflect growth characteristics, which can include small elevations, depressions, stains and also scratches. These could be described as “fingerprints” of nature – which actually underlines the uniqueness of each individual pearl.

Nevertheless, due to its rarity a flawless surface is at the top of the rating scale. Another special feature of Conch pearls is their porcelain-like appearance. It gives them a certain coolness – in the particularly attractive contrast to the flame structure.


DAMAGES The number and characteristics of the growth characteristics have a direct effect on the value of
the pearl: small jumps and other characteristics reduce the value.

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