Having caught the eyes of humanity since the Neolithic Period, amber is one of oldest gemstone used by humans. Not only has amber been part of our history, this warm stone captures history in time capsule in palm of your hands. As such, this guide will gently give you a hand in buying amber, a very affordable stone.
Considered a semi-precious stone, amber does not have a straightforward valuation compared to others. Many factors can affect the price. The best way is think in terms of categories like clarity and inclusion. One category may value a certain feature more than another category, depends on what the buyer is looking for.
Amber comes in various shades of yellow, orange, and brown. The classic color is yellow-orange, sometimes called honey amber. Rich honey with a dark tone is preferred. On the other hand, shades of brown that can demand a high price is cherry or cognac amber which has a slight red tint like brandy; also known as red amber. Black amber – actually dark brown – is rare. Amber from the Baltic region is considered to have the best overall color.
There are also green and blue amber stones display their colors under natural light. The green coloration is thought to be from plant pigments in resin, while blue amber only comes from the Dominican Republic. These two colors are very rare and expensive. However, rich primary color is preferred over rare colors.
Amber is not often faceted. Round and oval shapes in cabochon form is the standard to maximize the mass. Beads are usually made from lower quality stones, often used for necklaces and bracelets. Large pieces can be used for carvings.
Not a clean gemstone, amber can be transparent to cloudy to opaque. In general, a clear and clean amber is more valuable than cloudy and opaque ones. Amber from the Dominican Republic tend to have a higher transparency than Baltic varieties. However, unlike other gemstones, high clarity is not golden standard.
Related to clarity, but deserving its own section, inclusions are what sets amber apart from other gemstones. Inclusions are often judged as a separate category; independent of color or clarity. Many things can be trapped inside the fresh resin like bubbles, sand, plant materials, insects, arachnids, and even small reptiles.
With that in mind, the most famous inclusions are insects like mosquitoes, made popular by Jurassic Park. Ants and flies are popular as well. Sought by both scientists and collectors, well preserved and visible animals can make a “dirty” amber more valuable than a clean one. Plants and other foreign objects do not fluctuate the pricing much but they can be quite beautiful, especially ancient flowers. As a side note, Dominican Republic amber tend to have more inclusions than any other regions.
Small bubbles usually devalue the amber. However, a large bubble, 0.5 to 2 mm, surrounded by transparent body is prized due to the ability to refract lights to enhance the color and luster of the amber.
Lastly, microscopic bubbles throughout the amber can cause the stone to appear cloudy, even milky; sometimes called bony amber. The creamy patterns can make the stone look like a frozen latte coffee or modern art piece. Beautiful egg yolk and butterscotch amber can worth more than ones with good clarity without inclusions.
Many amber gems are treated with either heat, oil bath, or both. Oil bath and heat treatment reduce the cloudiness – increasing clarity – by evaporating tiny bubbles. Heat treatments also make the color darker. Green amber, for example, is often made by heating one side of an average amber and covering up process with a bezel in a jewelry. Most green amber sold are treated; natural green is very rare.
Buyers should look out for ambroid stones, which are pressed smaller pieces of amber using heat and pressure – amber softens at 150°C – to form a larger piece; sometimes called “genuine” amber to install confidence in the lower price. Chemical adhesives can be used to bind the pieces together as well. Ambroid often has visible division lines and layers.
In addition, flawed amber with cracks can be filled with copal, which is a much younger version of amber. While some low quality pieces are coated to improve the color.
Unfortunately, there are numerous imitations in the market. Processed copal, through autoclave, can be sold as amber, especially a problem in Europe. Phenolic resin, casein plastic, celluloid plastic, and glass are common materials used to make imitation amber.
Luckily, there are many ways to test authenticity. The rub test can quickly distinguish between amber and glass. Since amber is negatively charged, rubbing it with a soft piece of cloth, like wool or silk, will produce static electricity while glass will not, then place the piece near your hair to observe any attractions.
Another quick test is to shine an ultraviolet light on the piece. Real amber and copal will have some fluorescence properties like yellow, blue, green, and orange.
The classic test is the saltwater test but amber, copal, and plastics – like polystyrene – will float while glass and other heavier materials will stink. Of course, this will not work with jewelry. To make the solution, add about 2.5 tablespoon of salt to a cup of glass of water.
For distinguishing between amber and copal, there is the acetone test. Acetone will not have an effect on amber. Copal and some plastic, however, will weakly dissolve in acetone, causing a sticky surface. In addition, copal is much softer and will can be scratched easily with a fingernail.
Another test, while a last resort, is the hot needle test. Heat the tip of a needle red hot then poke the stone. Amber has a piney smell when burnt. In fact, amber is used as incense. Fake pieces will have a plastic or electrical smell. Unfortunately, real amber can crack in the process due to the high heat.
Inclusions can be used as a form of authenticity. Verified animals and plants are a sure proof but will require a trained professional. Be cautious of insects with nicely folded wings. Real insects will show some signs of struggle like spread out wings. Any modern looking inclusions or large animals will most likely to be fake. Always approach inclusions with some caution.
Again, amber is a soft gem that can be scratched so care must be taken when wore in active jewelries like rings and bracelets. Amber should be kept away from gasoline, alcohol, perfume, hairspray, and other caustic solutions. Some alcohols can stain or cloud the amber. Store these gems separately like pearls. Prolonged water exposure will ruin the polish. In addition, amber should be kept away from fire because they can burn.
As you can see, depending on what you are looking for, amber does give buyers an option on what they want. Whether it is a clear colored gemstone, a time capsule, or an unique stone that resembles contemporary paintings. Amber will be sure to please any buyer.