20 minute reading

Introduction | cornflower

In AD 1484, the Florentine painter Botticelli painted the birth of Venus. In the picture, Venus stepped on a shell, and the wind blew her from the waves to the seaside. On the right, the goddess of spring greeted her.

Among them, the clothes of the goddess of spring are decorated with blue flowers, which is the beautiful cornflower.

Centaurea is a flower from Leng Yan, which is produced in Europe and likes to bloom in cold regions. It is often seen in the Caucasus, Siberia and Central Asia Plateau.

There is a kind of sapphire named after this flower. Because the color is similar to that of cornflower, this blue sapphire of cornflower is also called "cornflower sapphire".

If you want to know about this baby with the unique texture of cornflower sapphire, come down with me ~

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Cornflower sapphire

Cornflower sapphire belongs to corundum mineral, which is cornflower blue. Just as pigeon blood red is synonymous with top Burmese ruby, cornflower sapphire is synonymous with top Kashmir sapphire color.

The name cornflower is named after a plant whose color is like cornflower. It is a kind of compositae plant with slender, elegant and colorful flowers. As the national flower of Germany, it is the symbol flower of the noble royal family.

The cornflower sapphire is considered to be the best sapphire in the world. It has strong blue and purplish tones, velvet colors and purplish tones.

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The origin of cornflower sapphire

At present, the main producing area of cornflower sapphire is Kashmir, and the price of cornflower sapphire produced in Kashmir has always been in the first place. Kashmir is to sapphires what Gu Mo is to rubies and Muzuo to emeralds, all of which are symbols of top producing areas.

High-quality Kashmir sapphires can present rich purplish blue and velvet texture. It comes from inclusions in precious stones, and the color bands and snowflake inclusions in cornflower reduce the transparency of sapphire, which is the most direct factor to create the unique velvet effect of Kashmir sapphire.

Now, apart from Kashmir, there are very few cornflower sapphires produced in Sri Lanka, Madagascar and Myanmar. No matter where the cornflower is produced, it can be certified as "cornflower" by international authoritative jewelry appraisal institutions, which is the most perfect proof of its color.

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Centaurea sapphire certificate

GRS certificate

As one of the most authoritative laboratories in the world, the certificates issued by GRS are very representative. On the GRS sapphire certificate, there are four most noteworthy points: weight (weight), color (color), comment (evaluation, whether it has been treated or not, etc. ) and Origin (origin)

GRS used to classify the color of cornflower loosely, and many sapphires with velvet feeling can be classified as "cornflower". GRS divides cornflower sapphire into four grades, namely, light cornflower blue, cornflower blue, deep cornflower blue and Kashmir blue.

Now GRS has tightened the naming range of cornflower, and now the common cornflower is blue (GRS-type "cornflower").

△ "cornflower" sapphire, burnt, produced in Sri Lanka.

The most common treatment method of sapphire is heat treatment, and if it is written in the comment and evaluation department: no indication of heat treatment, it means that it has not been optimized. If the evaluation is H, heat treatment is carried out.

Guild certificate

"Cornflower" and GUILD also have their own standards, which should be a purplish blue, giving people a unique texture like hazy velvet. The color scale belongs to bright blue and strong blue. Centaurea, like sapphire, has no requirement for the place of origin.

Guilds, like GRS, also pay attention to four points: weight, color, comment and place of origin.

GUID classifies the color of sapphire into five grades, namely, light, medium, thick, bright and dark.

It is worth noting that not every sapphire can determine the exact origin.

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The reason why cornflower sapphire is precious

Mining difficulty

Kashmir is located on the border between India and Pakistan, and the dispute over its ownership has a long history. At the same time, its geographical environment is special, with an average elevation of more than 4000 meters. It is in a state of low temperature and severe cold all the year round, and the suitable mining time is only 2-3 months every year.

In addition, the transportation, electricity, telecommunications and other infrastructure on the mountain are very primitive and backward, and advanced large-scale machinery and equipment can not be transported up the mountain, so it is difficult to explore and mine in the cracks of the mountain by manpower. However, it is precisely because of this special geographical condition that a special kind of sapphire-Kashmir sapphire was born.

Unique inclusion

Kashmir sapphire has the characteristics of fine filiform inclusions arranged in parallel, which is different from sapphires in other places. It can show the silky velvet texture in the hard and strong metallic texture of sapphire. This combination of rigidity and softness can make anyone who watches deeply moved.

Limited reserves

Kashmir sapphire mine was discovered in 1879, but its official mining ended in 1889. Because the reserves are very limited, it was excavated in 10. In recent years, the depletion of mineral resources in Kashmir has doubled the value of unburned sapphires in Kashmir.

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Optimal treatment of cornflower sapphire

As one of the most popular gemstones, the output of natural high-quality sapphire cannot meet the huge market demand. Gemmologists will improve sapphires in various ways to obtain a large number of high-quality sapphires. The most common improvement method is heat treatment, that is, "burning". Sapphire is colored under the joint action of iron, iron, titanium and titanium * *, and the valence states of iron and titanium in the sintered sapphire change, so does the color.

The appearance of heat-treated sapphire is almost the same as that of natural sapphire, but it still leaves clues. Because corundum has stable properties, it needs high temperature above 1000 degrees to achieve color change effect, so there will be some more obvious changes than heat-treated aquamarine;

There is also a common treatment method of sapphire, which belongs to the upgraded version of heat treatment. The coloring elements Fe2+ and Ti4+ diffuse into the cut sapphire at high temperature. This method is called diffusion treatment. Sapphire * * *, in addition to the characteristics of heat treatment, due to the slow diffusion of elements, the color is only a thin layer on the surface, concentrated on the edge line.

Attention! Diffusion treatment is different from heat treatment, and the sapphire treated by diffusion cannot issue a natural certificate.

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Cheats to buy cornflower sapphire

Color grading

Color is one of the most important factors affecting the value of sapphire. In the international market, Royal Blue and Centaurea are the two most widely recognized classifications, but they are mainly described by certificates such as Gubyrin, SSEF, GRS and Guild.

Place of production

There is no doubt that Kashmir is the most commercially valuable sapphire producing area, but it has long since disappeared due to the depletion of mines. Today, there are more and more sapphires from Myanmar, Sri Lanka and Madagascar.

With or without heat treatment

Heat treatment can improve the color of sapphire and optimize the purity. For the same quality sapphire, the price difference between heat-treated sapphire and untreated sapphire is obvious. Wearing heat-treated sapphire every day is definitely a cost-effective choice. If it is a collection, try to choose untreated sapphire.

With or without heat treatment.

Cutting is the second life given to gems by human beings, and a good cutting ratio can enhance the value of gems themselves. Gems usually choose to give up high-quality cutting for care. When buying sapphire, you can be a little more tolerant of cutting workers, but the ratio should not be too bad.

If you want to know more about other jewels, you can leave a message backstage ~

See you next time!