Rubies have long been valued for their incredible hardness and bright color. Unlike some gemstones, they are not graded on a precise, universal scale, but there are still several characteristics most jewelers use to rate a ruby's quality. Learn how to identify the quality of a ruby, select a setting for a piece of jewelry, and find out more about how rubies are mined or manufactured. Some ruby mines are associated with human rights abuse or environmental disasters, but there are several alternative sources that avoid contributing to these issues.
Steps
Evaluating a Ruby
- Select a carat that suits your budget and preference. Carats (c) are a measurement of the gem's size. In general, the larger the gem, the more expensive it is. However, there tend to be significant price jumps at 1, 3, and 5 carats will likely get a better deal if you select a 0.9c, 2.9c, or 4.9c ruby instead.[1] Remember that carat is a matter of aesthetics and practicality as well as value; someone with slender fingers or less ostentatious tastes may prefer a smaller gem.
- As a rough guide, a one-carat natural ruby that costs less than $250 is likely considered "commercial quality" instead of "fine quality." At $700 and up, hold it to a high standard. At $10,000 per carat and up, the ruby should be exceptional and rare.[2]
- Laboratory-made rubies tend to be sold for about 85–90% of the price that a natural ruby of the same quality would fetch.[3]
- Because larger rubies are rare, the price increases faster than the size.[4] A commercial-quality five-carat ruby may sell for ten times as much as a similar one-carat ruby, while a fine-quality five-carat ruby (which is quite rare) may sell for twenty-five times as much as a similar one-carat ruby.[5]
- Choose a cut. The cut of a gem describes how the gem has been shaped by a jeweler. The general shape is a matter of preference, although most rubies are cut as oval, cushion (a rounded square), or round. Heart or emerald (a rectangle with cut corners) are other relatively common options, but due to lower demand they may be a little cheaper compared to a gemstone of similar quality cut to a different shape.[6][7]
- Select a color. Ruby catalogs or websites may list this under color, or under hue. While pure red and purplish red rubies are the most prized varieties, high quality rubies exist in orange-red, rose, or pink as well. Selecting a color is a matter of preference.[8]
- If you are interested in pink rubies, look for pink sapphires as well. Sapphire and rubies are made from the same mineral, corundum, and classified as one or the other by color. Pink gemstones can be classified either way.
- Pink rubies may be in higher demand in Asia than in Western countries, and therefore worth more on that continent.[9]
- Some companies will try to describe the color based on the area of the world it came from, but this system is not accurate.
- If buying online, find a company with a return policy. While you can select the basic characteristics above while shopping online, it is extremely difficult to judge a ruby in more detail from a photo. Online gem salesmen may include information using the metrics described below, but even if they tell the truth, you may not find the ruby attractive when it arrives. If you must buy a ruby online, always make sure there is a return policy, and look up reviews of the company online to avoid scams. When the ruby arrives, judge it using the criteria below, and send it back for a refund or replacement if it doesn't match your standards.
- Hold the ruby in bright light. Inside the ruby, you may see one or more black or grey patches, called extinctions, where the light doesn't reach. The more of these there are, the lower the ruby's value.[10] Move the gem around in the light to see how visible the extinctions are from different angles. If you greatly dislike this trait, lighter-colored, shallow-cut stones tend to have fewer extinctions, but may have other problems, such as windowing (a transparent appearance, like looking through a window) and less brilliance.[11]
- The exact effect of inclusions on the ruby's price is somewhat subjective.
- Check the saturation. This metric is also called color purity or intensity, and should be included with the ruby's description. Vivid rubies have the richest color and are the most valuable, with strong rubies close behind. A medium, fair, or weak saturation means the ruby's color is masked by significant shades of brown or gray, making the color less distinct.[12]
- These ratings are assigned based on the judgement of the jeweler, not on a scientific measurement.
- Look at the ruby's tone. The tone of a ruby is a description of the amount of color present, ranging from very dark to very light. Medium tone rubies tend to be the most valuable, but this is up to personal preference.[13]
- Evaluate the ruby's clarity. Many rubies contain inclusions, or visible materials trapped inside the gemstone. Most commonly, a clear stone is more valuable. However, some ruby collectors appreciate the unique appearance a stone's inclusion gives it. Silky filaments of a mineral called rutile can create a sheen that is highly valued.[14] If these filaments are arranged in a star pattern, the ruby is a rare and valuable star ruby.
- There is no standard ruby clarity grading system. One common system rates the gem from 1 (perfectly clear) to 4 (many inclusions).
- Another common system rates them from F (flawless), VVS (very very small inclusions, difficult to see under magnification), VS (very small, visible under magnification), SI (small inclusions, barely visible to the eye), and I (inclusions easily visible to the eye).[15]
- Understand ruby treatments. Natural, untreated rubies are rare and expensive. Almost all rubies are heat-treated by the jeweler to intensify the color. This treatment is widely accepted, since it does not affect the stone's durability and improves its appearance. However, if the gem has been treated with surface diffusion or flux healing, extra material has been added to correct flaws in the ruby. These rubies tend to be much less valuable due to the temporary nature of the treatment.[16]
Choosing a Setting
- Select a metal based on preference and budget. Rubies are often set in white gold, but the metal you choose comes down to personal preference. If you are buying the ruby as a gift for someone, try to find out which metals are used in her other jewelry.[17] Lower carat precious metals are cheaper, but may be less lustrous or more capable of tarnishing.
- Display large gemstones in a prong setting. In a prong setting, metal claws hold the edge of the gemstone in place. This keeps the gemstone secure, and is a popular option for larger gems.[18]
- Use a bezel setting to hold gems in place. A bezel, or metal rim, fits tightly around the gemstone to hold it in place. This is another common setting for large gemstones, as is the half-bezel that fits around a portion of the gem.[19]
- Explore other options for rows of stones. If the items of jewelry has multiple smaller stones, it may not require one of the above options to keep it secure. Explore designs such as pave (small, precious metal balls), channel (a groove containing the stones), or invisible (using grooves cut into the gemstones to attach them without a metal perimeter.[20]
Learning about Ruby Sources
- Consider a lab-created ruby for low-priced quality. Rubies created in a laboratory are chemically identical to natural rubies, and therefore are just as durable and attractive. They are almost always cheaper than a natural ruby of similar quality, because the manufacturing process is cheaper than locating and mining natural rubies.[21] Lab-created rubies are an especially good choice if you are concerned about the negative human rights and environmental impact of ruby mines, which can be considerable.
- These are often called synthetic rubies. Don't confuse these with imitation or artificial rubies, which are not real rubies and are much less durable and bright.
- Star rubies are considered highly attractive, but natural star rubies are extremely rare and expensive compared to lab-created ones.[22]
- Look for "recycled" gemstones. About 98% of all rubies that are sold have been on the market for decades, since rubies are extremely difficult to destroy. Some companies specifically market some of their gems as "recycled" stones, sourced from public and retail owned jewelry, arguing that no new environmental impact is produced.[23]
- Critics note that purchasing new rubies supports gemstone mining communities.
- Learn about rubies from Myanmar. Most of the world's rubies come from Myanmar, the country formerly known as Burma. While older rubies may come from the famous Mogôk valley, they are now more typically from the region of Möng Hsu.[24] Due to the history of the region and the many famous rubies that were mined there, Myanmar rubies have a special cachet. However, due to human rights abuses by the government of Myanmar, the importation of new games from the region is banned in the United States and Canada, and was banned in the recent past by the European Union.[25][26]
- The purplish-red rubies known as "pigeon's blood" rubies come from this area, and are extremely valuable.
- Consider other source countries. Sri Lanka (Ceylon), Thailand, and several African nations export rubies, or have in the past, but these sources tend to ebb and flow as new mines are discovered or emptied. None of these sources are as famous as Myanmar gems, but some of them may be preferable for human rights or environmental reasons. The governments of Tanzania, Ghana, and Zimbabwe are all attempting to regulate the environmental impact of mines with limited success, as the individuals or small groups involved do not have the money to comply with environmental regulations.[27] Rubies mined in the United States are subject to environmental regulation, but they only make up a small fraction of the world's rubies.[28]
Warnings
- Just because a specific type of ruby is rare, expensive, or in high demand does not mean it will suit everyone's taste. Don't be afraid to pick the one you find more attractive, or that you think the gift recipient will.
Sources and Citations
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source How to of the Day http://ift.tt/1DQlmkU
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