ARAGONITE: Is There A Rare Faceted Gemstone Or Etsy Fraud?

I saw a ring on etsy that is VERY expensive.  It's advertised as Aragonite and is described as being a one-of-a-kind gemstone, Pleochroic (see below), and so very rare due to its "birefringence" which the seller described as meaning that the stone exhibited "different colors on different facets."  (And that is NOT what the term means....see below!)  The gem in this ring was even given a "name" --- you know, like the Hope Diamond or the Timur Ruby.  They claim this particular stone is "one of the rarest faceted gemstones on earth"!  In doing a simple Google search, no such named Aragonite appears, except the one listed on etsy.  The "name" of this gemstone is also the ancient name of the Kingdom of Aragon, which is simple history and is now known as the region of Aragon, Spain.   And this supposed rare and exquisite "gem" is mounted in a Sterling Silver setting.... well, if this were indeed an expensive gemstone ring (listed at well over $20,000!) then it most certainly would have been set in platinum, or white gold, or yellow gold.  So that's a giveaway right there that something in the milk ain't clean, so to speak!

If you Google images of Aragonite, you can see what it really looks like.

What is Aragonite?

Aragonite Crystal-Spain

Aragonite is described as "a mineral consisting of calcium carbonate, typically occurring in white seashells and as colorless prisms in deposits in hot springs."  It is formed by biological and physical processes, including precipitation from marine and freshwater environments.  The common mineral Calcite is also made of calcium carbonate.  Per www.minerals.net, "There are many Aragonite crystals sold to collectors that are in fact really calcite."

There are many Aragonite crystals sold to collectors that are in fact really Calcite pseudomorphs after Aragonite - See more at: http://www.minerals.net/mineral/aragonite.aspx#sthash.KiuX60SO.dpuf

There are many Aragonite crystals sold to collectors that are in fact really Calcite pseudomorphs after Aragonite. - See more at: http://www.minerals.net/mineral/aragonite.aspx#sthash.KiuX60SO.dpuf

There are many Aragonite crystals sold to collectors that are in fact really Calcite pseudomorphs after Aragonite. - See more at: http://www.minerals.net/mineral/aragonite.aspx#sthash.KiuX60SO.dpuf

It's named Aragonite after Aragon, Spain, where it was first discovered.  It is also found in the Czech Republic, Mexico, Austria, and even Carlsbad Caverns here in New Mexico, which form as stalactites.

It is often used in replicating reefs in aquariums.

Aragonite is the main component in such organic gems as pearls, coral and mother-of-pearl.  It is Aragonite that gives the nacre its iridescent look.

Aragonite Needle Spray - Austria

Aragonite forms in many environments, and can be banded as well as nearly colorless or brown.  It can be found as colorless, white, brown, grey, yellow, red, pink, green, blue, purple, orange. 

Colorless, white, brown, gray, yellow, red, pink, purple, orange, blue, green - See more at: http://www.minerals.net/mineral/aragonite.aspx#sthash.KiuX60SO.dpuf

It is actually Aragonite that is sold as "Mexican Onyx" or "California Onyx" or even "Onyx Marble" and "Suisan Marble".

Flos Ferri Variety

It is VERY soft and brittle, with a Mohs hardness of 3.5-4 which makes it unsuitable (as a gemstone) for jewelry.   Window glass has a Mohs hardness of 5, so this is much softer than glass.   In fact, the Flos Ferri variety of Aragonite will break when touched!   As a crystal, it has a luster that is described as "vitreous, dull" and is brittle.







What is "Birefringence?

Well, first we have to discuss refraction.  When light passes through something, such as a gemstone, or even a glass of water with a straw in it, the light rays are "refracted" or bent at an angle.  Light passes more slowly through water which is why the straw seems bent.

Birefringent Aragonite on Graph Paper

Each gemstone as its own refractive index, and this is used to identify gemstones.  Some gems are singly refractive----diamonds, spinel, and garnet, and also opals and organic gems (pearls).  Most gemstones are doubly refractive.  This means that a beam of light is split into two beams, each beam traveling at a different speed and path through the stone.  "Birefringence" is the measurement between the two beams.  Most gemstones' birefringence is hard to detect with the naked eye.  Sometimes it's very strong, and if not cut properly, can result in a blurry looking stone. 

So this particular etsy seller said their stone was "Birefringent", as if that was rare.  It's the most common!  And it has nothing whatsoever to do with varying colors....because that would be called "Fire" or "Dispersion" in the jewelry world.

What is Dispersion or Fire?

When the white light rays are refracted inside the gemstone, the rays are split into the colors of the rainbow (like a prism).  This colorful effect is called "Fire" in the jewelry industry.   Diamond has the highest Fire of all the natural (non-synthetic) gemstones.

Dispersion - Aragonite

A genuine Aragonite, which again is really too brittle to wear as jewelry (and is more of a collector's gem), exhibits certain qualities, as all individual gemstones do.  Per http://www.classicgems.net/gem_aragonite.htm,
Aragonite exhibits a Dispersion (or fire) is considered "weak".   The dispersion for a CZ is high. Pleochroism (or the ability to be different colors at different angles) is NONE.  This seller is claiming it IS pleochroic!  Not possible if it's Aragonite.  And all the fire "dancing" around the stone pictured on etsy?  Not possible if it's Aragonite. 


What About Aragonite on Etsy?

I did a quick search for "Aragonite Ring" on Etsy, and there were 59 items found.   58 of these items are definitely and truly Aragonite!  They look like rough crystals, or opaque and banded stones in the various natural colors of Aragonite (such as blue, yellow, brownish, pinkish).  And they're lovely!  But this one ring... could it be Aragonite?  Or could it be a "jonquil" CZ set with two clear CZ baguettes?  Some other stone?  The seller showcases this ring with different lighting, and the "flash" or "fire" in the stones looks like a CZ, and nowhere are pictures or descriptions of "fire" in faceted Aragonite.   So luckily I live near Rio Grande Jewelry, THE major supplier to the jewelry industry world-wide, and I asked one of the gemologists there to take a look at this listing.  Their opinion was that without testing, they couldn't be sure what it was, but it didn't look like any Aragonite they've seen.   They said the pictures show a very clear stone (not blurry, such as seen in the Aragonite pictured above) with the fire exhibited in many stones, most particularly Cubic Zirconia which is available in many colors, even color-shifting CZ stones.  I of course am not going to pay over $20,000 to purchase it in order to have the ring tested.  (Especially from a seller who will NOT accept a refund even for misrepresented stones; i.e., fakes---as their one-star feedback states!)   And the clear baguettes are obviously CZ and in NO way are "clear Aragonite".

Prices Per Carat

Per the website gemsociety.org, there are suggested retail prices per carat for gemstones.  These are RETAIL, not wholesale.  For Aragonite, it is listed as between $26 and $260 per carat for Aragonite that is 5 carats and up. 

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It's so sad to see gemstone claims like this online, as it taints the reputation of all online jewelers and Etsy sellers.  I would not suggest purchasing that ring, and for that price, you could purchase---from a reputable jeweler---a diamond or other gemstone, set in gold or platinum,  that would increase in value. 

BUYER BEWARE!!

Colorless, white, brown, gray, yellow, red, pink, purple, orange, blue, green - See more at: http://www.minerals.net/mineral/aragonite.aspx#sthash.KiuX60SO.dpuf