Knowing The Jewelry » gemstones

How to Determine the Price Value of Color in Gemstones

MS Prasaja — Wed, 26 Aug 2009 00:31:05 +0000

Gemstones may come in a rainbow of colors, but the jewelry industry uses a universally defined system to grade it. Color accompanies clarity, cut, and carat weight to make up the 4C’s and can greatly affect the aesthetic value of gemstones. Many people mistakenly believe that darker is always better, but what they should truly be looking for is brightness and vividness. Use the following tips to accurately evaluate the color of gemstones by yourself.

Evaluating Color of Gemstones by Using the GIA or Munsell Color Grading System

Although there are many and equally effective color grading systems in use today, the GIA or Munsell system is a good primer to start with. It utilizes a plastic set made up of 324 color pieces to serve as standard references. If a certain color is found missing from the system, interpolation can be performed to come up with more than 760 additional shades.

The GIA or Munsell system is made ideal for judging the color of gemstones because they are built with 3D plastic pieces that resemble faceted gemstones.

Elements of Color

The color of gemstones should be judged according to the three main elements:

Hue – This is the first impression we obtain from viewing colors. It is what makes rubies red, sapphires blue, emeralds green, and amethysts purple. Hues have a natural order and they are red, yellow, green, blue, and lastly purple. Numerous shades can be achieved by mixing together any two of these hues.

Chroma or Saturation – This element refers to the vividness, purity, strength, or intensity of a given color. Gemstones with low chroma are referred to as weak while those with high levels of saturation are called vivid or strong. Saturation of colored gemstones may be classified as the following in ascending order: grayish or brownish, slightly brownish or grayish, very slightly grayish or brownish, moderately strong, strong, and lastly vivid.

Value or Tone – This is what makes you think of red as light or dark red. Gray as well as black and white are referred to as neutral or achromatic colors because they don’t possess any hue. Colors with hues are referred to as achromatic colors. GIA uses a numerical system, with its written definitions, to evaluate neutral and achromatic colors alike. For transparent colored gemstones, however, only grades or tones two to eight are considered.

0 colorless or white

1 extremely light

2 very light

3 light

4 medium light

5 medium

6 medium dark

7 dark

8 very dark

Treatments Used for Changing Colors of Gemstones

When shopping for colored gemstones, another question you should definitely ask and one you couldn’t evaluate without a definite honest answer is if the color is natural or applied. There are several commonly used and accepted color treatments that are applied to gemstones in order to change their appearance like heat treatment, irradiation, dyeing, and straining.

Heat Treatment This is the most commonly utilized and one of the oldest treatments for modifying the color of gemstones today. This treatment may use temperature ranging from 100 degrees Celsius to more than 2000 degrees Celsius and improves color distribution as well as reducing visibility of flaws.

Irradiation Low or high electromagnetic waves or energy particles are used to change the color of a given gemstone. Like heat treatment, there is little remaining evidence that could clue a buyer to its use.

With irradiation, certain gemstones have their colors enhanced. Bleached, off-color pearls will obtain a darker tint. Brown or light yellow diamonds can become colored. Light yellow or colorless sapphires may turn yellow to orange, but the change could only last for days. Colorless quartz may turn into smoky quartz. Colorless as well as pale pink and dark blue beryl may become yellow or maxixe-type respectively. Time, light, and heat may, however, cause the color for treated beryl jewelry to fade.

Dyeing and Straining This is the major term used to refer to various techniques utilizing a foreign and differently colored substance to modify the color of a given gemstone. A combination of techniques, like dyeing and clarity enhancement for beryl, may be used to improve overall effects. In coating, the application of a second substance is only done on the surface.

Practice makes perfect so browse jewelry shops to familiarize yourself with the various signs that could alert you to the use of applications and treatments on gemstones.

The Gem Stone Mining and Making Process

MS Prasaja — Thu, 16 Oct 2008 05:36:07 +0000

So you’re wondering how exactly your jewelry came to be. Well, that’s a normal question any jewelry enthusiast would ask. You do question how these gems are placed into metal. You also question where exactly these gems came from.

There are gem stone mines everywhere around the world. The most popular are in Brazil, Canada, Mexico, Uruguay and Africa. There are also mines in Europe and the United States, depending on what kind of gem stone you are looking for.

Amethyst

Amethyst is the most valuable kind of quartz. It is found everywhere around the world. For this very reason, it is one of the most affordable. The quality of amethyst is quite unique, depending on where it was obtained. Amethyst that are found in the United States are larger compared to those found in Africa. However, the latter has higher saturation when it comes to their colors.

Amethysts with the highest saturation are those found in Australia. There are also amethyst found in Brazil are usually large and have hues and cuts.

Emerald

Emeralds are mostly found in Mexico. Two main sources are the mines in Guerrero and Vera Cruz. Emeralds found there have the tendency to have lighter shades and are clearer than those found in other countries. The stones have lighter hues and the crystals are phantomed with a transparent interior and a saturated exterior.

Emeralds that are found in Guerrero are saturated dark green. They have a visible termination of their interior color saturation and exterior transparency. The highly saturated emeralds are the most elegant.

Sapphire

The most notable source of Sapphires are those found in Brazil from Minas Gerais, Bahia, Maraba and Rio Grande do Sul. Among those containing the best sapphires are the large pockets that are formed by the volcanic material.

The sapphires that are produced here vary in their color saturation which ranging from pale up to medium blue. Those that are navy blue are the sapphires that have the highest saturation.

Diamond

Africa is known to be a producer of diamonds, thus the inspiration of the recently released blood diamond. There are diamond deposits in Zambia and Namibia. The diamonds found in Africa can be as large as an egg and are outstandingly clear.

Jade

The United States has various gems. In Maine, North Carolina, Pennsylvania, Montana and Colorado, the most popular stone is the Jade. The color depends from the medium saturation. It may be smoky or translucent, depending on where it was obtained.

Jade from Maine and North Carolina are usually dark while those found in Montana or Colorado have a green tint.

Now, the next question, how are the jewelry made? Diamonds, emeralds, sapphires, amethysts, and jade are only a handful of precious gemstones out there. Some of them are very valuable because of their rare appearance.

How are these gemstones formed? Well, they are formed underneath the Earth. The process involves vary in each gem stone. The stones react with the minerals, specifically water. This is how they are dissolved. When the solution evaporates and cools down, these minerals are formed.

The water then mixes with the silica-rich rocks like sandstone. This produces the gemstones like amethyst, opals, agates, sapphires, jade and topaz to name a few. When the copper-rich rocks mix with the water, it bears the minerals like turquoise, malachite and azurite.

Emeralds and tourmalines are formed from rain water or the water that is from cooling bodies like magma that is mixed with the minerals and crystallized in cavities or open cracks. These spaces are filled with minerals which create the hydrothermal deposits needed in the formation of these gem stones.

There are also gemstones that are formed directly from the mantle. They consist up to 70% of Earths total mass. They are usually made up of magnesium, silicon, iron, oxygen, silicate and aluminum compounds. The upper layer of the Earths mantle has a volume of the olivine which is quite common in the whole procedure.

Whenever you hear the word metamorphic it means the change of form of these rocks. Metamorphic gems are garnet, emerald, ruby, aquamarine, sapphire, onyx and zircon. They are formed over a long period of time because they wait for the rocks to be altered with such pressure and intense heat in order to interact with the other solutions.

Tips When Buying Gemstones

MS Prasaja — Tue, 14 Oct 2008 09:35:40 +0000

People have always fallen in love with gemstones. That is because these items are almost always breath taking and are truly exquisite. Gemstones are valuable because naturally, their market appraisal is high. Thus, it is expected that you need to allot a significant investment when you aim to purchase any type of gemstone.

When buying gemstones, it is important that you first seek to be knowledgeable about the task. It is easy to acquire such items on the market if you have plenty of money. But if your resources are limited and you are aiming for the best deals, then, you need to get to know several guidelines of how the purchase can be made worthwhile and practical.

Here are some tips.

- Observe and look at the gemstone of your choice at all possible and viewable angles. You should get a thorough ocular examination of the item to find any defects like uneven color distribution, presence of color zones, cutting defects and apparent inclusions. Defects found can reduce the value of the gemstone. If you want to purchase an item at significant discount, be observant enough and look out for any sign of defects.

- Be interested but don’t let your enthusiasm show. You are advised to maintain your composure no matter how breath taking a gemstone. This strategy would help you maintain a sound and reasonable judgment over the jewelry.

- Don’t be intimidated by the overall appearance and presence of the broker. If the gender, nationality and age of the broker distract you, chances are greater that you would only nod to what the broker has to say and forget to affirm your side or your judgment. If that happens, you will lose your power to secure a bargain.

- Be patient to present your offer for the gemstone at the end or near the conclusion of the negotiation. You should appear and sound firm on your stand so that the broker would think your standing offer is the ultimate concession you could possibly offer.

As you buy the gemstone, aim to keep it as a priced possession. You should make sure to constantly update yourself about the valuation of your possession so that anytime, as the need may arise, you could always get the choice to dispose it. Gemstones are beautiful. They will never fail to mesmerize the eyes of the beholder, so keep it safe the way you guard your life.

Categories of Gemstones

MS Prasaja — Thu, 02 Oct 2008 04:37:18 +0000

There are many different types of gemstones, and knowing the different categories can help a collector or enthusiast expand his repertoire greatly. Some precious gemstones are so unique in chemical composition and crystalline structure that they fall into their own categories, while others can be collectively lumped into one. Here are the major types of precious and semi precious gemstones:

Diamond – diamond is it’s own type of gemstone, and is well known for being the hardest naturally occurring substance known to man. Diamonds are primarily high-carbon crystals that were fused under extremes of pressure and heat.

Diamonds themselves aren’t especially rare, with thousands being mined throughout the world every year; however, large diamonds of high quality are extremely rare, and it is these which are well known for setting the standards of diamond gemstones as the world’s most precious stone.

Corundum – this is the second hardest type of gemstone, and is primarily defined as being composed of aluminum oxide and various trace minerals. The trace minerals create different types of corundum, and perhaps the two most well known examples of this type of stone are rubies and sapphires. Rough corundum isn’t used as a gemstone, but is used as an industrial strength abrasive element due to it’s tough nature.

Chrysoberyl – this is the third hardest gemstone, and while it uses aluminum oxide as a base element like corundums, it has high quantities of beryllium mixed in with it. Appearance wise, chrysoberyls often come in a green to yellow shade, though their appearance is best known for having the tendency to actually change color somewhat under different types of lighting. Cat’s eye and alexandrite are two common chrysoberyls used in jewelry.

Quartz – this is actually one of the most common types of mineral in the world and comes in a wide variety of colors. It’s main tendency is to form in hexagonal shapes and it makes an excellent prism if unflawed.

The main reason quartz can still be categorized as a valuable gemstone is that, while it IS easy to find quartz stones, finding a large, perfect, and unflawed quartz crystal of jewelry quality is extremely rare. Some examples of quartz gems commonly used in jewelry are onyx, amethysts, citrines, and carnelians.

Beryl – this is a stone well known for it’s beauty and has elements in common with both chrysoberyl and quartz. It’s basic chemical composition is similar to chrysoberyl, with beryllium and aluminum prevalent but mixed in with other trace elements. It’s basic crystalline structure, on the other hand, is closer to quartz, being hexagonal in nature.

At it’s simplest, beryl is actually transparent, while it’s other colored variants include emeralds and aquamarines. It can come in yellow and red shades as well, and these are referred to as “red” or “yellow” emeralds.

Jade – this is one type of gemstone originally lumped into the same category as beryl. The main reasons for this are because both can be mined in similar places and they possess similar textures, opacity, and appearance (just different colors).

Later on, chemical analysis showed that the elements which made up the different forms of precious jade, namely nephrite and jadeite, were different from beryl completely, thus earning jade it’s own category among gemstone collectors. Jade based stones are often composed of calcium and magnesium elements.

Feldspar – this is a unique type of gemstone whose base material is tectonic in nature. It is often found in areas of high geographic instability like earthquake faults and volcanic chains. Feldspar’s basic chemical composition is made up of very common elements found deep inside the earth’s crust.

What makes it valuable as a gemstone is the same factor that makes a diamond much more valuable than a lump of coal that would normally contain the same elements as diamond. That is, with sufficient heat and pressure applied, the tectonic elements fuse together to make a rare red gemstone known as feldspar.

Organic Gemstones – the most famous examples of this are pearls and amber. Basically, organic gemstones are ones which occur naturally in organic sources as opposed to mineral sources. Pearls are formed from oysters, while amber is a yellow stone formed from fossilized tree sap. While not gemstones per se, organic gemstones are still used heavily in jewelry so are included in this list.