Diamonds Exclusive




1. Measure the diameter of any other ring that fits a given finger. Read out the ring size that matches the diameter.

2. Measure a finger’s circumference. Read out the size matching the circumference.

Please remember that ring sizes are measured up to 1/10 of millimeter. So the difference between two adjacent sizes might be so small that insignificant and be in the measurement – ballpark.


88 15,29 mm48 mm 0,602 in1,89 in
8,75 J 15,49 mm48,7 mm 0,61 in1,92 in
9,255 9 15,70 mm49,3 mm 0,618 in1,94 in
10K 15,90 mm50 mm 0,626 in1,97 in
10,51016,10 mm50,60 mm 0,634 in1,99 in
11,25 L 16,31 mm51,20 mm 0,642 in2,02 in
11,756 11 16,51 mm51,90 mm 0,65 in2,04 in
12,5M 12 16,71 mm52,50 mm 0,658 in2,07 in
13,2513 16,92 mm53,10 mm 0,666 in2,09 in
13,75 N 17,12 mm53,80 mm 0,674 in2,14 in
14,507 14 17,32 mm54,40 mm 0,682 in2,12 in
15O 17,53 mm55,10 mm 0,69 in2,17 in
15,7515 17,73 mm55,70 mm 0,698 in2,19 in
16,25 P 17,93 mm56,30 mm 0,706 in2,22 in
178 16 18,14 mm57,00 mm 0,714 in2,24 in
17,50Q 18,34 mm57,60mm 0,722 in2,27 in
18,2517 18,54 mm58,30 mm 0,73 in2,29 in



Gemstones will always maintain their actual value which is not dependent on economic crises, turning points in history, currency exchange rates or falling prices of securities. Diamonds are comparable to a separate, universal currency not restricted by any borders.


Only few stones deserve to be called precious. These are: diamonds, ruby, emerald, sapphire, chrysoberyl and opal. Other natural stones that are less durable and softer are referred to as semi-precious stones. These include, for example, topaz, garnet, aquamarine, chrysolite, turquoise, zircon, tourmaline, hyacinth, spinel, amethyst, rock crystal and morion.

Although diamonds have always been a symbol of authority and power, real diamond fever began in the 19th century and it still continues. Large diamonds are one of the most precious jewels in the world. The largest diamond found in South Africa in 1905 had a mass of 3106 carats. It has been cut into 103 pieces and polished. The biggest piece of that diamond of 530.2 carats has been set into Queen’s sceptre. It’s called the Great Star of Africa (Cullinan diamond).


Diamonds are indisputable kings of gemstones; their name comes from the ancient Greek αδάμας – adámas "unbreakable". Diamond is an allotrope of carbon, where carbon atoms are evenly arranged. It is the hardest known material in the world. On the Mohs scale of mineral hardness it has a hardness of 10 (hardest). Diamonds have already survived 3 billion years in nature. The temperature of 1325°C and the pressure of 50 thousand kg/cm2 (comparable to placing the Eiffel tower on our hand) transformed carbon into this wonderful nature creation that will dazzle us with its shine till the end of the world.


Gemstones’ prices increased significantly in recent years. Gemstone investment rates can be either high or low but will never bring loses. Polished diamonds cost anything between several hundred and several million dollars per carat. Their value is constantly increasing because of growing demand and limited supply. The amount of natural diamonds is limited and not all of those found are suitable for polishing.


Traditional equity investments are becoming increasingly uncertain and global markets are no longer stable. The uncertainty of current economic situation contributed to the development of alternative forms of investment, among which diamonds are the most reliable form of saving. It is a real investment and not temporary virtual value recorded in registers of banks that may go bancrupt. The value of a gemstone depends more on its individual characteristics that on the market situation.

However, such investments require proper knowledge and caution; stones should be chosen with utmost care. Our company provides specialist advice and helps to choose the perfect diamond. We can also create a unique piece of jewellery with your diamond because diamonds are meant to dazzle others rather than be locked away in a safe.

Gems can be purchased from specialist jewellery companies. This is the only way of buying that carries no risk of fraud, especially when a diamond comes with an international certificate of authencity issued by one of the 3 most important gemmological laboratories: HRD, IGI or GIA. The certificates are globally recognized and certified diamonds may be several times more expensive than not certified ones. MARCELLO STAVIORI makes every effort to ensure that stones we use are of the highest quality and their origins meet the UN criteria -that they come from countries free from armed conflicts.


Diamonds price depends on 4 factors, known as “4Cs”: carat, clarity, colour and cut. The bigger the stone is the higher the value per carat gets. The price per carat of a 1,00-1,49 carat stone is on average 3 times higher than the price per carat of a 0,30-0,37 carat stone of the same colour and cut. Diamonds are classified by colour into classes D-Z. Clear ones are the most expensive (D to I), and yellow ones are classified J to Z. Prices of yellow diamonds can be several times lower than clear diamond prices. There are also blue, green, pink, brown and black diamonds.
Diamonds are the rarest natural minerals. The best diamonds come from Angola, Namibia and Russia. Raw diamonds are matt and dull. It is the polish that brings it to life. Only the best diamond cutters can shape it to make it glow and shine.




The weight of a diamond is expressed in carats. One carat = 0,2 grams and one carat equals 100 points. Which means that 10 pointer diamond weights 1/10 of a carat usually denoted as 0.10 ct.


All diamonds have traces of their growth history. Microscopic inclusions are an integral feature of gemstones. The clarity scale reflects the size, number, location and visibility of the characteristics when examined with a loupe 10x. The very best and rarest clarity is loupe clean. Most inclusions, however, are not visible to the naked eye. Diamonds that have no inclusions visible to the unaided eye are also of excellent value.


Most diamonds are colourless to slightly yellowish. The colour grade is determined by comparison with a series of masterstones, the best grade being colourless. With an exception of intense colours such as pink or light blue which are also very valuable. Diamonds can occur in all sorts of colours, ranging from brownish to striking yellows, purple, red and blue. These are called “fancy colours”


Brilliant cut diamonds are referred to as round diamonds. Other popular shapes are oval, marquise, pear, heart, emerald and princess. Diamond cut quality is determinative for the brilliancy and the fire of the diamond. Full cut diamond has 58 facets ( 56 facets, table and culet.) Low quality cut can depreciate the value of a stone even more then 50%. Evaluation of the cut is the most crucial part in diamond evaluation process.




Sapphire is a variety of corundum, the next hardest natural stone after diamond. It’s usually blue but there are stones in all colours except red. The blue colour comes from iron and titanium. Some sapphire varieties get asterism from the titanium dioxide impurities present in them. The most precious sapphires are blue and come from Kashmir, Burma and Thailand. Stones from Sri Lanka are brighter and those from Australia are darker, often greenish.


Rubies are a form of corundum. Their colour can by anything from bright red to almost purple shade of red. Their red colour comes from chromium. Like sapphires, these precious stones get asterism. The most precious rubies are red with a shade of blue. This colour is characteristic to rubies coming from Burma. Rubies have always been highly valued. Beautiful, large stones can be much more expensive than diamonds. Rubies can be found in Burma, Sri Lanka, Thailand, Tanzania an Afghanistan.


Emerald is a green, the most valuable type of beryl. Emeralds, as well as diamonds, sapphires and rubies are one of the most durable materials known to mankind. It’s mostly light to dark green, sometimes grass green. Its colour comes from admixture of chromium and vanadium. Value of emeralds is based on their beautiful colour and transparency. The most expensive emeralds are dark green, with no cracks or cloudiness. Large, unblemished stones can be more expensive than diamonds. Until the 19th century global market was dominated by Colombian emeralds. Their deposits were later discovered in the Urals, US, Austria, South Africa, India and Zimbabwe.




The oldest gold jewellery is about 6000 years old. Our jewellery will be equally old in 6000 years’ time! Goldsmithing flourished in Europe in the 16th and 17th century when jewellery in similar style was produced. Our design is unique and unrepeatable.


Gold is a relatively soft metal so it’s alloyed with other metals, such as silver, zinc, copper and palladium. They not only make the gold harder, but also change its colour and smooth its surface. Gold’s assay indicates percentage of pure gold is in the alloy. For example 0,585 assay means than in 1000 units of alloy’s mass there are 585 units of pure gold. Until early 20th century gold was mostly assayed in carats. According to this system, gold 0,585 assay is 14 carat gold, 0,750 equals 18 carats and 0,333 equals 8 carats. Pure gold theoretically is 1000/1000; however, as it’s impossible to remove all impurities, the purest gold is 0.999. Gold with this assay is considered pure, 24 carat gold.

Gold’s colour doesn’t affect its price and is simply a result of colour enhancing treatment that consists of increasing the amount of other elements in the alloy. For example white gold has more silver in it than palladium and copper. The most popular colours are yellow, white, pink and red.


Typical bracelet and necklace sizes

Every range of jeweller has its most common and most sought after sizes:
Women’s necklace – length – 420mm
Women’s bracelet – length – 190mm (also 180mm and 210mm)
Men’s chain – length – 550 mm (also 500mm and 600mm)
Men’s bracelet – length – 210mm to 230mm


How to care for jewellery...


Authentic gold or silver jewellery, especially one with precious stones, is like a dress from Chanel so treat it with respect.

Gemstones and natural pearls are particularly vulnerable to loss, cracking, chipping, being treaded down or other damages caused by everyday use. You should take off your jewellery when you are doing housework, going to bed or exercising.

You should be careful when wearing fine, delicate chains. They can be damaged or deformed by a slight pull, even during sleep. When you take off your chain remember not to curl it or bend it too tight as it may cause a permanent deformation.


1. The beauty of jewellery is durable, but also delicate and fragile. You can enjoy the glow of your favourite jewellery for a long time if you follow simple rules. Most jewellery can be damaged by direct contact with water. Water can affect jewellery is different ways; it may lose its shine or discolour. This applies particularly to pearls and mother of pearl as they are exceptionally delicate and sensitive. Getting marcasite jewellery wet can result in stones falling out. You should always remove all your jewellery before bathing or washing up.

2. Detergents in cleaning products and personal care products like hair sprays, deodorants and perfumes can cause discolouration. Jewellery is made either of pure metal or alloy of different metals that can react with various substances. Chemical products can harm natural or organic stones (pearls, ambers) by tarnishing them or causing delamination. Therefore, you should protect your jewellery from a direct contact with such substances by, for example, applying beauty products before putting on your jewellery.

3. Storing jewellery is also very important. Each piece should be wrapped in a soft cloth and sealed in a separate bag. It will help to avoid damage and exposure to dust etc. A good place to store your jewellery is a jewellery box. It is also recommended to have our jewellery professionally cleaned from time to time.

4. The best thing you can do at home is dust your jewellery regularly. It’s best to use special jewellery wipes. You shouldn’t attempt to clean your jewellery using cleaning product or polishes.


MARCELLO STAVIORI offers superior gold products, such as fine jewelry, custom made jewelry, designer jewelry and high-end jewelry. We offer original investment jewelry with precious stones such as diamonds, sapphires and rubies set in perfect 18 carat gold. Each piece is unique and created according to customers taste. Diamonds and other stones are micro-set which ensures outstanding durability and precision. MARCELLO STAVIORI investment jewellery is a timeless masterpiece that is designed to dazzle everyone around.

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