What Determines an Emerald’s Value?

Emeralds are considered one of the “big three” in precious gemstones, a classic jewel regularly used in high-end jewelry. But what differentiates one emerald from another? There are many factors that determine their value. If you’re in the market for emerald jewelry, here’s what you need to know about the most desirable qualities of this beautiful gemstone.

What Determines an Emerald's Value | Auction King


Generally speaking, when you’re shopping for gemstones, the most valuable stones are those with no visible inclusions. However, that isn’t really the case for emeralds, because all natural emeralds have some inclusions that are visible to the naked eye or with a jeweler’s loupe. In fact, most emeralds receive some treatment to reduce the appearance of these inclusions during the lapidary process, which is not considered to affect the value of the stone. Only a synthetic emerald (much less valuable) might be perfectly clear—some are even given artificial inclusions to look more genuine. Thus, inclusions are a sign of an emerald’s authenticity. Emeralds that are considered “eye clear” are extremely rare, and quite valuable. It is only when inclusions are so numerous that they negatively affect the stone’s transparency that they can reduce an emerald’s value.


An emerald’s brilliant green color is produced by trace amounts of chromium, vanadium, and iron. An individual stone can have a varying amount of each, and thus an emerald’s color can range from bluish green to yellow-green. The exact hue may hint at a stone’s origins—for example, emeralds from Zambia tend to be on the blue-green side, while emeralds from Brazil and Colombia are a more pure green. In general, the more intense the color, the more valuable the stone. Stones that are extremely light or extremely dark (so much so that the transparency is reduced) cost less per carat.


Emeralds are often cut in a rectangular shape, known as an emerald cut, to both enhance the natural color of the stone and to protect against chipping or breaking. Although they are resistant to scratches, emeralds tend to be somewhat brittle, and their natural inclusions can make them prone to fracturing. However, whatever the cut of the stone, it should enhance its natural sparkle and color.


While you can find emeralds in sizes ranging from truly tiny to huge, very fine grades of emeralds over one carat are rare. In general, a larger emerald will be worth more if its color and clarity are also good. If you have two stones with the same overall color and clarity, the larger one will be more valuable.

The overall value of an individual emerald is determined by a combination of these factors—a small but unusually clear emerald of gorgeous green may very well cost more than a much larger light-green emerald that looks cloudy from numerous inclusions. The best way to get a feel for the way these combinations can affect price is to shop around and compare prices.

Auction King regularly stocks emerald bracelets, necklaces, rings, and earrings in a variety of sizes, cuts, and styles. Our live online auction gives our buyers an opportunity to find exquisite pieces at below-market values. Sign up for a free online account today and browse our selections. The piece you’ve been looking for may be just a click away!

What Determines the Value of Tanzanite

Tanzanite, discovered only fifty years ago in the foothills of Mount Kilimanjaro, is a relatively new entry to the list of desirable gemstones. Given its short history compared to more familiar gemstones like emeralds and diamonds, it’s not unusual to encounter some confusion about what factors contribute to the value of an individual tanzanite.

What Determines the Value of Tanzanite | Auction King

While many of the categories that determine the value of other stones—cut, clarity, and carats—also apply to tanzanite, it’s important to know that color is the most important thing to consider with this rare gemstone. The finest tanzanite not only displays an intense blue or blue-violet color, but it is also pleochroic, meaning that it displays flashes of different colors depending on which direction it is viewed from. In fact, its unusual and beautiful color is what has propelled its unparalleled rise in popularity since its discovery. The most valuable tanzanite has a deeply saturated color; while paler stones are also attractive, they do not command the same price as more vividly colored gems.

Tanzanite is cut into a variety of shapes for jewelry. The primary consideration in determining a good cut is showing the stone’s color and pleochroic properties, which means the cutter must properly determine the direction of crystal growth to achieve the best effect. A secondary consideration is the overall size of the stone. The cutter will generally try to achieve the largest possible cut stone from the raw material, unless this will result in significantly inferior color. A well-cut tanzanite will be brilliant and symmetrical, no matter what the shape chosen.

Because of the geological processes that form this stone, tanzanite can readily be found without inclusions visible to the naked eye. As with other gemstones, tanzanites with fewer inclusions are more valuable, and those that do have inclusions that can be seen without the aid of a jeweler’s loupe sell at a significantly lower price.

As with other gems, when all other factors are equal, a large tanzanite will cost more per carat than a small one. However, the most intense colors tend to be seen in sizes of five carats or more; stones of one to two carats tend to be much lighter in color than larger stones. In large sizes, the best-quality tanzanite can sell for $700 per carat or more. While tanzanites are available in a variety of sizes, gem-quality stones over thirty carats are quite rare.

One final factor to take into consideration is tanzanite’s rarity. The entire world’s supply of tanzanite comes from a single location only one and half miles square. While experts may disagree on exactly when the mines will run out, they agree that it will happen. Therefore, prices can only be expected to rise.

You may believe that a high-quality tanzanite is beyond your reach, since it is so rare and valuable. However, you can still find excellent deals on large, dark-blues tanzanite by shopping at auction. The live online auction at Auction King regularly features beautiful tanzanite necklaces, rings, bracelets and earrings for a fraction of their retail price. Sign up for a free online account today and get this rare gemstone before it’s gone for good.