买 变色宝石

What is a Color Change Gemstone?

Of all the different types of gemstone, just a very few have the ability to change color in different light sources or different times of the day. Not just changes in tone but a complete shift in color - some dramatic as in Alexandrite and others more subtle as with Fluorite.

How does a Gemstone change color?

First, a brief science lesson. In the simplest of terms, (I am not a very good science teacher) whenever we look at an object what we see is reflected light. If, for example, we look at a red apple, waves of light which include all the colors of the rainbow hit the apple. All the colors are absorbed except the red which reflects back to our eyes and the apple appears red.

This is how we see most gemstones. In the same way an apple reflects the red color so does a fine ruby - the other colors of the spectrum are absorbed by the stone and a deep rich red bounces back. It is the molecular structure of an object, be it an apple, a ruby or a leaf, that causes different colors to appear.

Different light settings can affect the colors that we see. Full daylight contains a lot more blue and green waves while candlelight or incandescent light has much more red in it. The angle of the sun, the temperature of the air, time of the year and cloudy or clear days can all affect the depth of color we see.

The crystal structure and the chemical make-up of certain gemstones will make the different lighting schemes even more exaggerated than normal colored stones. Let us take a look at one of the most spectacular color change gemstones, Alexandrite.

The cause of the color change in Alexandrite is the presence of chromium ions, this impurity allows light to be absorbed half-way between green and red to our eyes. In natural daylight there is more green and blue light (and our eyes are very sensitive to green) so we see the stone as green.

In candlelight or incandescent light there is much more yellow or red light and little green to reflect so we see red as the dominant color. There is a theory that because Alexandrite splits the green and red so decisively we see either one color or the other with no gradients and the change in color is very striking.

What are the most popular Color Change Gemstone types?

Alexandrite is the most famous, expensive and dramatic color change gemstone but genuine examples are very hard to find and demand a very high price. There are a few other gemstones which can also change color:

• Color Change Garnet
• Color Change Sapphire
• Diaspore
• Color Change Fluorite
• Hyalite Opal
• Color Change Spinel

What shape are Color Change Gemstones?

Color Change Gemstones are always facet cut to show off the exciting color change at its best. All color change gemstone varieties are high quality stones with excellent clarity and durability so they are available in all the usual shapes such as oval, round, cushion and octagons.

What are the spiritual benefits of Color Change Gemstone?

Color Change Gemstones will have all the powers of their gem type, a few examples:

• Alexandite/Chrysoberyl - Creativity, Imagination and Intuition
• Sapphire - Wisdom and Abundance
• Garnet - Grounding and Energizing
• Fluorite - Calming and Soothing
• Diaspore - Intuition and Manifestation

In addition there is the power of color to be considered.

• Red represents strength and passion
• Green represents growth and money
• Yellow represents success and optimism
• Orange represents enthusiasm
• Purple represents power and spirituality

Color Change Gemstones will possess the power of two colors.

Read more about Gemstone Meanings here.

How much are Color Change Gemstones?

Color Change Gemstones are priced on the usual 4Cs - color, clarity, cut and carat size - plus the contrast in the change of color and the gemstone type.

Undoubtedly, a genuine Alexandrite with a notable switch in color, good clarity and a quality cut would be considered a very expensive gemstone - regularly in the top ten lists of most valuable gemstones and worth well over $10,000 per carat.

Color Change sapphires are probably just below alexandrite in value but they are often found in small carat sizes and deep blue sapphires or the padparadscha sapphires are actually worth more. Most color change sapphires will fall into the $50 - $200 per carat range unless it is a very large stone or has a phenomenal color.

Color Change Diaspore tends to be a very clean stone with colors that change from a lemon yellow to a peachy orange shade. The price per carat of diapore can increase dramatically as the gemstones get bigger - smaller gemstones less than a carat in weight are around $30 - $40 per carat but stones larger than 5 carats can leap to $300 - $400 per carat.

Color Change Garnets are the most varied of all color change gemstones and the primary colors can affect the price considerably. Pink, orange, brown, yellow, honey and pinkish colors are relatively common and are approximately $100 per carat. Any garnets that are predominantly blue can command much higher prices.

Despite their bright blue to violet colors, color change fluorite are probably the cheapest of the Color Change Gemstones and fine examples range from $20 to $30 per carat.

What jewelry is Color Change Gemstones suitable for?

Gemstones are rated on Mohs hardness scale for their suitability for use in jewelry with diamonds at the top with a score of 10. Anything above 7 is perfectly fine for most jewelry items including daily wear pieces while gemstones under this rating should have protective settings.

All gemstones will be fine for pendants, necklaces, earrings and brooches as they are far less likely to get many knocks or bumps.

The various gem types that are occasionally found as Color Change Gemstones include:

• Color Change Sapphire - Rated 9
• Alexandrite/Chrysoberyl - Rated 8.5
• Color Change Garnet - Rated 6.5 - 7
• Color Change Diaspore - Rated 6.5 - 7
• Color Change Fluorite - Rated 4

Color Change Gemstone History

Finnish mineralogist, Nils Gustaf Nordenskiöld, is the man usually credited with the discovery of Alexandrite. He thought he had found a new source of emeralds at first until it turned red a bit later in the candlelight!

Legend has it that he discovered it on Czar Alexander II's birthday and so named the gemstone in his honor.

Although it can been found in various locations around the world - most recently a pink version in Afghanistan - Diaspore as a gemstone was first found in the Anatolian Mountains of Turkey. In was sold to intrepid tourists in the 1970s before coming to the notice of gemologists in the 1990s.

Since 2006 it has been sold as Zultanite, Csarite or Color Change Diaspore as an exclusive product of Turkey.

Color Change Gemstone Treatments

As far as we are aware most Color Change Gemstones are not treated in any way to enhance their appearance. Sapphires can be heated to boost color and clarity but this not always the case with color change sapphires. Garnet, fluorite and diaspore are never treated.

Any treatments our gemstones receive will be fully and clearly disclosed.

Where are Color Change Gemstones found?

Color Change Gemstones can be found all over the world although certain examples seem to be fairly exclusive to one or two spots.

• Color Change Sapphires - Thailand, Sri Lanka, Tanzania, Madagascar, Australia
• Color Change Garnets - Tanzania, Madagascar and Mozambique
• Color Change Diaspore - Found only in Turkey
• Alexandrite - Originally from the Ural mountains in Russia but now found in Brazil and Sri Lanka
• Color Change Fluorite - Mostly from Brazil

Birthstones and Anniversaries

Many of the Color Change Gemstone varieties are also birthstones:

• Sapphire - September
• Garnet - January
• Alexandrite - June
• Hyalite Opal - October

They are often great traditional gifts for wedding anniversaries:

• Garnet - 2nd Anniversary
• Sapphire - 5th, 45th and 70th Anniversary
• Hyalite Opal - 14th Anniversary
• Alexandrite - 55th Anniversary