Gems

Padparadscha – Lab Certification Roulette

Padparadscha – Lab Certification Roulette

Guest Blog by Inken Krause, Enhoerning Jewelry

Entire book chapters and countless longish essays have been written about the ideal color of Padparadscha sapphire and the cultural history of this special color descriptor so full of romantic idealization and metaphoric meaning. Now Yvonne has asked me to edit a short guest blog (emphasis on short), so I will try to work on a more practical question.

What does a sapphire look like that will, in all likelihood, be ennobled as Padparadscha by the most important American/European* gem labs?

Several labs, AGL among them, agreed that this 2 ct unheated Ceylon sapphire is a Padparadscha. The perfectly balanced mix of orange and pink leaves very little room for doubt.

This 2 ct Padparadscha was most likely tested for color stability by AGL, although they do not explicitly mention this on the report. I hope they will start doing this on future reports. 

Color -- Hue
Modern definitions of Padparadscha ask for a pink-orange (called type “sunrise“) or orange-pink (called type “sunset“) color. Purists tend to prefer the sunrise type. The color mixture between pink and orange should be well balanced. If either pink or orange is very weak, most labs do not grant the pad label, and any hint of brown is a deal breaker for most of them. Some labs are very strict and exclude any yellowish (not orange) or lavender-purplish (not pink) color. In my experience, the New York based AGL is rather tolerant about purplish hues, but absolutely unforgiving about brown. Of the American labs, GIA tends to be the strictest when it comes to hue (see the round stone example below).

AGL certified this 4 ct unheated Ceylon sapphire as Padparadscha, GIA disagreed and called it “pink sapphire“.



This 2 ct unheated Ceylon sapphire was certified “Pad“ by AGL, and the color is so well balanced that almost any other lab would follow. It leans slightly to the orange side, making it a sunrise Padparadscha.





This 4 ct unheated Ceylon sapphire was certified as Padparadscha by an Asian lab, but AGL (with good reason) decided it is only a ‘light purple’ fancy sapphire, although there is indeed a very slight orange modifier.



Color -- Tone
Tone is the least critical aspect of Padparadscha color. Most labs will accept a wide range of tone (lightness/darkness), as long as the tone corresponds well to the saturation level. Higher saturation can have higher tone. A low color saturation with a high value of tone often leads to a brownish or grayish appearance of the gem. A sapphire with a strong grayish appearance will not be considered a Padparadscha by most labs.

This 2 ct unheated Ceylon sapphire was certified Padparadscha by several major labs, including AGL. It shows a slight grey modifier, but the orangey-pink color predominates in daylight.



Color -- Saturation
Saturation is the most tricky aspect of Padparadscha certification. Almost all Western gem laboratories ask for a light (“pastel“) to medium saturation in pad sapphire. The color should be “delicate“. However, in practice, lab certification can work differently. Many labs routinely reject pink-orange/orange-pink sapphires and do not grant the desired color descriptor if they find the saturation to be too light! (Happened many times to me and my stones). However, it is very rare that they reject a sapphire as a non-pad because of too high saturation, unless there is a brownish modifier. Almost no lab can resist the beauty of an intensely to vividly saturated pink-orange/orange-pink sapphire, even if these stones do not meet their official requirements for (lower) saturation. AGL seems to be notorious for this paradox, but I have seen it on lab reports by GRS and even the highly respected Gübelin lab as well.

This 1 ct unheated Ceylon sapphire was certified by AGL as “Pale orange-pink“. Because of the “pale“ it did not pass as Padparadscha but was labeled fancy sapphire.



Color -- Stability?
The color of a Padparadscha needs to be stable and may not fade over time and/or in the absence of UV light. Color stability in pad (and other color fancy-) sapphire is a hot topic right now and deserves another blog entry of its own. In the meantime, please feel free to read some latest research here: https://www.ssef.ch/wp-content/uploads/2018/03/2018_Padparadscha_colour_stability_facette.pdf

Most of the laboratories mentioned in this text routinely do color stability tests on potential Padparadscha sapphire and do not grant the color designation if a stone does not pass. If you buy a Padparadscha these days, make sure that it comes with a reputable lab report that is not older than a year. Even the most respected laboratories did not test for Padparadscha color stability until a couple of years ago.

This 5 ct Padparadscha was tested for color stability at Lotus Gemology, although they do not explicitly mention this on the report. I hope they will start doing this on future reports.



Geographic Origin?
For Padparadscha purists (like me) a real pad is from Ceylon (Sri Lanka) or from Burma (Myanmar). The very rare Padparadschas from Burma are incredibly beautiful. However, many mining locations produce Padparadscha sapphire, for instance Madagascar. A fair number of fancy sapphires from Madagascar do not pass the “pad test“, however, due to color stability issues. Pad-like sapphires from Umba, Tanzania, often do not get certified as Padparadscha due to brownish modifiers (or, sometimes, too much saturation).

Treatment?
Again, Padparadscha purists (like me) have their own view on things and think that only an unheated pad-color sapphire is a real Padparadscha. All of the labs mentioned in this article, however, certify heated (heat-only!) sapphire as Padparadscha, too, if the color is right. None of the labs mentioned in this article will give the precious title to sapphires that have undergone Beryllium-heating or any other invasive treatment.

Three Ceylon sapphires, all unheated/untreated. The middle one shows almost perfect Padparadscha color. The one on the left does not show enough pink. The one on the right is rather high in saturation for a Padparadscha, but shows a good balance of orange and pink (all of these are available through Cecile Raley Designs).




This 1.99 ct unheated/untreated Ceylon sapphire is currently available in Yvonne‘s Etsy shop. It is of the “sunset“ type and has a good to very good chance to be certified as Padparadscha by, for instance, AGL.



* comments made in this blog entry apply, to the best knowledge of the author, to the following gem labs: AGL, C. Dunaigre, GIA, GRS, Gübelin, IGI, Lotus Gemology, SSEF; this blog article does not make any promises about lab results for your sapphire.

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Hunting for "Diamonds" in Herkimer

Hunting for "Diamonds" in Herkimer

I assume you've heard of the Herkimer diamond?  It's actually quartz and but nicknamed "diamond" because of its shape: double terminated (meaning with two points) and with 18 natural facets.  It was discovered in Herkimer County, NY.  The currently open mines are "Ace of Spades" https://www.herkimerdiamond.com/ and "Crystal Grove" https://www.crystalgrove.com/

I'd been wanting to go for some time and so this year when my travel buddy Jochen Hintze from Jentsch Minerals came to exhibit at the Edison Gem show, we decided to tack a short trip onto his stay and headed for St. Johnsville, NY on Monday April 8 for a two night stay on an organic farm (because why just stay in a hotel….right?).  I admit it was a bit chill with just a wood stove, no hot water and 35 degrees Fahrenheit at night. Who says I have to have all my adventures in Africa anyway?

After a relaxing evening (interrupted by trying to make the wood stove work) with local beer, home- made chili, several games of Ludo, and a chill morning brightened up by fresh farmed eggs cooked on a camping cooker, we headed out for Herkimer.  The Ace of Spades mine is located close to the center of town, and right behind the main building, for $10 a day, you can hit rocks with a rented hammer (they can be rented for $1).  The diamonds are hiding in little cavities inside, sometimes loose (these are called floaters) and sometimes attached to the host rock.  Whatever you find, you get to keep.  We found three attached to host rock (no floaters) - in about two hours - and only with some guidance about which rocks to split open.  So our treasure consisted in a find of about $2-3. 

At around lunch it started to pour so we ended up spending quite some time in the quaint shop.  We found out that in order to have a real bounty, you need to have the owners open up a larger pocket for you - they apparently know where those are, they will bulldoze the area and then split open the pocket in your presence.  If the pocket doesn't contain anything interesting, they will open up another.  But if it is too valuable, they keep it and give you another instead.  This decision is at the sole discretion of the owners, and the fun sets you back by $1700.  But to be fair, living off a mine like this isn't exactly easy and the owners say clearly that the activity of opening up a pocket is supposed to be for family entertainment, not for profit by expert miners or geologists.  So this isn't something we will undertake.  But we got some nice video for you of the hard work this kind of mining requires, and of course I also bought a few crystals and some faceted stones for you to purchase. 

I realize you can buy those directly elsewhere for less, so I am marking them up very low and you get the benefit of me having hand-picked each stone for cutting, excluding the included and brownish materials, making sure there's no window and no abrasion in the girdles (several gems had those) and picking gems that are easily settable in my designs. 

Here are some photos, if you'd like one of the more included crystals just let me know, it's yours free (shipping is free with any purchase or $3.50).  If you want me to get it drilled and made into a pendant, I'll have to charge something though.

 The inclusions, by the way, are.... you guessed it (not): asphalt.  Petrolium, in other words, or unrefined oil.

Jochen was actually very happy that instead of finding crystals, he found asphalt in host rock instead.  I have a lot of asphalt already, outside the house, mixed with gravel and flattened for driving, no host rock of course, but I still passed!  That's ok, I got my Herkimer "diamonds" instead.

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What’s up with all these “new” Emeralds: Emerald Origins Revisited

What’s up with all these “new” Emeralds: Emerald Origins Revisited
Panjshir Emeralds: these lighter minty green emeralds are mined in the Panjshir Valley in Afghanistan, and improved political relations have made these available in slightly larger quantities. My personal favorite, these gems are extremely vibrant and often cleaner than their counterparts. This website here has some fascinating videos of the mining process in Panjshir. We have some completely untreated material available in very limited quantity, and we can source more material if oil is ok. Continue reading

Padparadscha Sapphire – What’s the Story?

Padparadscha Sapphire – What’s the Story?

Every since Britain’s Princess Eugenie has been sporting a Padparadscha sapphire engagement ring valued at over $130,000, these lotus flower colored beauties have been all the rage.  Industry prices have actually risen as a result.  In terms of color, purists claim that a Padparadscha should combine peach-pink and orange tones, ideally mixed evenly (no color zones), and have light to medium saturation. But exactly how that looks is a point of contention.  The ideal comparison is the Lotus flower which it is named after.  Given the huge variation in both color and saturation of actual lotus flowers, it might be fair to say that this reference is more romantic than it is helpful.

Originally “pads” were mined primarily in Sri Lanka, and this is why “purists” still consider only a specimen with the famed Ceylon origin to be a true Padparadscha. Nowadays, however, gems from other regions with the same color characteristics, for instance from Madagascar or Tanzania, can be deemed a “pad” as well. Some gem dealers will refer to those as “African Padparadscha” but one should not rely on the nomenclature being exact. In any case, it is still true that a Padparadscha sapphire from Sri Lanka will command a premium in price, even if the color quality is the same as a comparable stone from Africa. Whether this is justified or not, the take-home message from this is: if a seller is asking an additional premium for the Ceylon origin of a Padparadscha sapphire, one should only pay the extra if the alleged origin is backed up by an origin report of a reputable lab (GIA, AGL, ...). 

 Traditionally only an unheated sapphire is eligible to be considered a “pad” but that has since changed s well.  Heating may turn an originally only very faintly peachy colored sapphire into a “pad.”  This should not command a premium in terms of price, however.  As to the nomenclature (is it a pad or not), I would probably stay away from the term, to be on the safe side.

 

GIA has a very interesting article on the historical development and currently use definitions of the term Padparadscha sapphire, which you can look at here: https://www.gia.edu/doc/Padparadscha-What-s-in-a-Name.pdf

According to the report, written by Robert Cownsingshield, no reliable laboratory criteria can be established to standardize the term Padparadscha – at least not one that all labs would agree on.  However that said, a color description can be given that will be used as a comparison base for color.  Here’s what Cownsingshield says about that:

It is GIA's opinion that this color range should be limited to light to medium tones of pinkish orange to orange-pink hues. Lacking delicacy, the dark brownish orange or even medium brownish orange tones of corundum from East Africa would not qualify under this definition. Deep orangy red sapphires, likewise, would not qualify as fitting the term padparadscha.

This definition is best applied by comparing to what the lab considers samples of the right color.  Unfortunately, some laboratories are much stricter in their application than others.  The strictest US lab is probably AGL at present. 

Candidates for the Padparadscha Label from our Collection - All Sri Lanka Origin, the rightmost stone is heated.

1.03 Ct. Sri Lankan Sapphire, 6.4 x 5.7mm, no heat Link here

1.56 Ct. Sri Lankan Sapphire, 7.5 x 5.7mm, heated, labeled "Pad" despite heat. 

 Oval Padparadscha Sapphire, Unheated, 6.67 x 5.36mm. Link here 

Now, it would be expensive both for sellers and buyers alike to have every single possibly qualifying sapphire evaluated by AGL.  So it is often left to gem dealers to decide how to classify their purchases, which is why it is so important for a buyer to find a reliable and also knowledgable source for their sapphires when it comes to the less valuable pieces (probably at a price over 1K, a declaration of “pad” should probably be verified by AGL.  My own source, as many of you know, is Dudley Blauwet, who has extensive industry experience and sources all his sapphires directly.  Here’s what Dudley has to say about the way he distinguishes a pad from a peach pink sapphire: 

https://www.youtube.com/watch?v=mx8eDQ4Px1A&t=1s

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Gem Lab Reports: Some FAQs

Gem Lab Reports: Some FAQs

As you’ve probably noticed, Cecile Raley Designs provides certificates with certain gems, or we offer to provide one upon request.  With more and more requests for certificates coming in, it’s time to review what these reports do for you and when you should get them. 

Gem Identification: This is probably the single most important thing a lab report can do for you.  A gem ID provides you with certainty that the gem you bought is what you thought it was.  It tells you that the gem is not synthetic or lab grown.

Specifications: A lab report also gives you the details about the gem, its shape, weight, cut, measurements, color, and variety (i.e. the sapphire variety of corundum).

Treatment: Not all treatments are mentioned in a lab report, or need to be.  Whether treatments are mentioned depends entirely on the gem and this can get complicated very quickly. Basic treatment, i.e. heat treatment of a sapphire, must be disclosed.  But this is not the case for an aquamarine or a tourmaline.  Why? In part this is because it cannot actually be determined if an aqua or tourmaline is heated.  The heating process does not leave any trace on these gems. Treatment is also disclosed if it can affect the value.  So, for instance, if a ruby is glass filled it has little to no value and if it is totally untreated it has high value. Note, however, that to detect different treatments, different techniques are needed.  Heat, glass fill, or surface enhancements like oil can be detectable under the microscope but it’s not possible to detect if borox was used in diffusion treatment.

Origin: Origin in gems is often very hard to determine and it is not always certain. Only fairly broad origin regions can be determined, not the actual mine or town where a gem came from, and for different gems different methods are needed.  Essentially one determines origin by identifying other trace minerals in the gems and locating its origin.  Alternatively, as with Russian demantoid, the types of inclusions can be a tell-tale sign of the origin.  With some gems, diamonds for example, origin cannot be determined at all.  We only know that certain colors, such as pink, mostly originate from a specific location, Australia in this case. And diamonds come from just about everywhere!  By contrast, other gems (like grandidierite and kornerupine) have only one known origin. It is also important to point out that gems under 3mm in size cannot be tested for origin (AGL won’t provide any reports for them at all).  These stones are too small to yield useful readouts, or to have any identifying inclusions.

 

Value: Most labs do not provide a value of the gem on their report.  Gem values constantly fluctuate so there’s no point in trying to nail it down.  Only appraisal labs, such as GAL, give you a value.  GIA, AGL and EGL do not.  The point of providing a value is to give an insurance company something to go by in case the gem is lost or stolen.  It’s not really to show the client that they got a good deal (or a bad one, for that matter).  And how is the value determined?  Gem labs find out the value by referencing quarterly price tables that list approximate values.  These values, in turn, are based on reported sales.  Price lists are only available for the most common stones.  For uncommon materials, the lab has to do research, i.e. looking at comparable gems on the internet or calling other labs and asking them if they have recently seen or valued a gem of that type. 

2013 Rapaport Diamond Report. You can find more information here: http://www.diamonds.net/Prices/RapaportPriceGuide.aspx

Sometimes, there’s no comparison base at all.  Cobalt spinel, grandidierite, benitoite and kornerupine are just some gems that have no prices available for comparison.

What does a lab report cost? The cheapest report I know of is the GAL mini cert which costs about $40 retail, and $80 for the full report.  The AGL gem brief is $70 for smaller stones, and a prestige report with origin is $220.  And if you have a gem pair each gem costs separately.  AGL won’t put both on one report.  GIA starts at $160.  AGL and GIA have a turnaround period of 3-4 weeks, GAL is faster – at least for me they are because I give them a lot of my stuff.

And now for the most important question: Should you get a report at all?  I would say no if your gem cost you less than $500.  We US sellers are bound by law to provide you with the merchandise we advertise so if anything is not as promised we have to take it back, and if fraud is suspected, we are in trouble.  Plus, lab reports can increase the asking price for a gem because the time and money of the report will now figure into the price.  This is especially true for  AGL and GIA reports.

That said, when you buy a diamond, it should pretty much always be certified, at least if it is more than half a carat.  This is for a different reason, however.  Diamonds are easy to identify, so you don’t need the report for that (you can get a diamond tester instead, or hold it to a flame if you suspect it’s moissanite – it will change color).  But because diamonds are expensive, a report, and in particular a GIA report, which is a very strict grading, provides you with assurance that you are paying the correct price.  While diamonds are not traded on the commodities exchange, they do have fairly fixed values, determined by the Rapaport diamond sheet.

 

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Rare Gemstones - A Seller's Market

Rare Gemstones - A Seller's Market

Anecdote:  in late summer I got a call for a 4+ carat lagoon tourmaline of a very specific cut and color, not too dark, etc etc.  Unsurprisingly, the potential buyer couldn't find such a stone anywhere.  I asked the buyer if they were serious about the purchase because it would be expensive and hard to find.  I come across about 100 lagoon tourmalines in that size a year at best and I know who imports them and the source.  I know Tiffany likes those stones too and they pay good money for them.  Out of those hundred or so stones, which is probably most of the annual production, 99% are not the specified color and cut.  Well maybe 98%.  But you get the idea.  Anyway I borrowed 5 stones to show to the client that came close.  No luck.  Again another stone, no luck.  It took at least a full day to get it all together, plus all the conversations.  The buyer grew frustrated, I tried explaining the search was impossible, got impatient with the client, the deal imploded.  Mutual unhappiness.

Lesson: I should have not taken on the search and explained from the start that I would not be able to meet the demands 100%.  It was not going to happen.  The client did not understand - or I failed to make the client understand - that sometimes it's not about the money.

This Cobalt Oval Spinel is old stock, there's currently almost no production

This Cobalt Oval Spinel is old stock, there's currently almost no production

Here are some other related things I've heard from customers:

"This stone is not blue enough.  I want to return it and look for a type of stone that's more blue." - said of a Vietnamese Cobalt spinel.

"What is your best price for this?"  Question about a hauyne that is irreplaceable.

"I'd like that stone to be .... : bigger."  Referring to red Burmese spinel.

I'm not the only one, I've overheard many statements like this at gem shows while I was quietly putting together my stash of purchases. 

This is a 7x5mm certified Hauyne. Clean specimens of this size almost never occur, and when they do, they are insanely expensive.

This is a 7x5mm Certified Hauyne. Clean specimens of this size almost never occur, and when they do, they are insanely expensive.

While I can certainly understand that questions must be asked, and while I know that bargaining is commonplace, when it comes to rare goods, they are based on a fundamental misunderstanding!

Consider the real estate market.  Do you ever go to an open house in an expensive community and ask to get something bigger?  Or ask for the "best price"?  No, because there will be many other potential buyers who are not going to ask that question.

Going back to the gem market, here's an anecdote related to me by a gemstone dealer at the Denver show.  A client approached him with a request for a stone he specialized in, very rare, very big piece.  The seller, who had bought up pretty much all the remaining supply of that stone some time ago, had one single piece available.  The price tag: $40,000.  The buyer balked and said he would look for something else somewhere else.  Came back a month later, unable to even get a comparison price, and bought the stone.

This is a 5x4mm Red Beryl. This is my only piece as the material is no longer on the market.

This is a 5x4 mm Red Beryl. This is my only piece as the material is no longer on the market.

Gem dealers who deal in rare stones know what they have.  They had the money to buy it, the goods are paid off so they don't owe anyone.  They will have already made some money on their gems, they are not desperate, and they are proud of their gems.  They do not have to sell!

Here’s another example. With many products you get a price match guarantee. Find the product for less elsewhere and your price is matched. Companies do this to keep your business because you could just as well go somewhere else. But if a gem dealer is the only one who has "the product", there’s no lower price to match. So there’s no point in asking for it. If the dealer really needs to sell, he or she may come down in price on his own. People often say that it can’t hurt to ask for a discount. But in a seller’s market it can.

https://www.etsy.com/listing/546385168/on-sale-benitoite-benitoite-shield-6mm

This is a 6mm Benitoite. No treatment. This is from old stock as these mines closed a few years ago.

5mm paraiba cushion Copper bearing paraiba

This is a 5mm Cushion Paraiba. It is a turquoise blueish color, a little cleaner specimen than others I've had in the past,

So let’s say you’ve already done your homework: you’ve looked up your coveted gem at a few websites, you have determined what size and color hue it comes in, you have checked availability and prices. Is there anything else you can do to sway the seller your way? I would say show that you have done your research. Most dealers love that you can appreciate what they have and they know it will save time and headache in the transaction. Refrain from asking for payment plans, it suggests that you are not in a position to make the purchase. If the seller wants you to have the gem and they trust you, they may offer it.  Don’t be afraid to say you need to think about it and walk away for a bit. Buyer's remorse sucks. If you hope for repeat business, make a smaller “good faith” transaction.

Ask for the stone to be put on hold only if you are sure you will take it. A seller who loses the opportunity to sell, especially at (gem) shows  that only last a couple of days, will not put a stone on hold for you again.

And most of all, remember: gems are not a "must have" item. They are beautiful and the can be a good investment. But no gem  is worth forfeiting an item you actually need!

How do you know if you are in a seller's or a buyer's market when you start making your inquiry?  Simple.  Start a search, go to eBay, Etsy, online sellers, go to the top dealers that you know, like maybe Pala gems, look at their collections, get the prices.  If you cannot find anything, or almost nothing, it's a rare stone.

Stones mentioned are available to check out or purchase on my Etsy Shop

Red beryl : https://www.etsy.com/listing/561016361/on-sale-red-natural-beryl-emerald

Benitoite: https://www.etsy.com/listing/546385168/on-sale-benitoite-benitoite-shield-6mm

Paraiba: https://www.etsy.com/listing/557094537/paraiba-tourmaline-cushion-paraiba

Hauynite: https://www.etsy.com/listing/512634598/on-sale-hauyne-hauynite-certified

Cobalt Spinel: https://www.etsy.com/listing/539524569/on-sale-oval-cobalt-spinel-cobalt-spinel

 

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Opals: Some thoughts on their special allure and their challenges for the jeweler

Opals:  Some thoughts on their special allure and their challenges for the jeweler

Opals:  Some Thoughts on Their Special Allure and their Challenges for the Jeweler

If you’ve been following my shop for a few years, you will notice that I have never carried a lot of opals – not until recently!  You may know of my dislike for Ethiopian opals but if not, here's why I don't really like them: I bought some Welo opals shortly after they initially came out and there was a bit of a craze – prices actually went up from a few bucks a carat to $50-70 per carat wholesale within a year or two.  Shortly after purchase, the opals started cracking and turning opaque.  Following common advice, I soaked them in water: Welo opals actually absorb water, unlike other opals, and I believe that they have an even higher water content as well.  Anyway, the experiment backfired; the opals dried up and cracked even more.  I threw them out.

Anecdote: an opal dealer friend of mine from Germany was offered the first rights to the mines in Ethiopia.  Juergen is his name, and he’s been working with opals for the past 40 years if not more. Juergen claims to have been the first white person on the ground to see them.  I’m not challenging this belief but Africa is a vast place and these things are hard to confirm.  He went ahead and had the rough tested, but found it too unstable to get into the business.  He passed.

Juergen is also my source for most of the opals that I now carry.  He specializes in Australian material but also carries Mexican fire opals.  He has a great eye for the material. 

Mexican Fire Opal

Mexican Fire Opal Pendant

In terms of pricing, the boulder opals I carry are a little cheaper than black opals.  Boulder opals still have the host rock in which they are found, which makes a sort of natural doublet. An 'artificial' doublet is created by gluing plastic onto the back of a very thin slice of opal to increase its color and strength but I don't carry these as they have little to no value.  Matrix opals, like Koroit opals, are a sub group of Boulder opals with the opal distributed as “veins” within the material, looking like a matrix.  I don’t like them as much because they have too much brown but some of them can be very pretty.

Boulder Opals from my Shop

Apart from boulder opals, my favorites are black opals.  Black opals are the rarest of all, they do not have any host rock, ideally they are thick, and their body tone is, as the name says, black.  They are Australian as well.  White opal is technically the same as black opal, the only difference is explained in its name.  The body tone is a milky white color, which brings out less of the play of color in the opal.

Black Opal Pairs

The most valued opals have the largest variation of colors.  Blue and green tones are the youngest in terms of geological age, red the oldest, making red the rarest of all colors displayed in an opal. 

Opal pricing can be very confusing, even to the professional.  Other than the few pointers I just gave, it is very subjective.  The ones most people like the most, however, tend to be the highest priced as well.

So, why do I not carry a lot of opal?  The short answer is that it is hard to work with.  Here are some reasons:

  1. Opal is very soft so it can break easily during setting, especially a hard metal like white gold. Back setting is easiest for that reason.
  2. Most opals have irregular shape, so I need to make the setting for each stone. That’s expensive of course. And it makes a bit of a mismatch in terms of pricing as well: boulder opals are often larger and you can get more opal for your money, but then you face the problem of having to set a big stone into a lot of gold and that makes your cheaper purchase a rather expensive one in the end.  Long story short, I don’t sell a lot of opals as a result.  I end up having to disappoint customers when they ask about setting.
  3. Opals are harder to care for than other stones as they shouldn’t be left to dry out, and, although we're talking in terms of decades, even a top quality opal will not last as long as most other faceted stones. So I kind of feel bad selling something that’s pricey, expensive to set, and not as long lasting.

Still, when I went to Vegas I just couldn’t resist the beauty of some of the pieces that Juergen showed me.  I’ve listed most of these but I held back my favorites (why I don’t know, I can’t keep it all!).  Here are photos and videos.  Listings are coming up, and I am taking requests.  Both of these are pairs, but I am willing to break them up if I get two interested parties.

 

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Russian Demantoid: What’s the Deal with Horsetail Inclusions?

Russian Demantoid: What’s the Deal with Horsetail Inclusions?

As many of you know, I have been selling quite a few Russian demantoids on my site in the last year.  Initially they came from only one source, old stock, topping out at (exactly) 3.2mm, no heat, and a very bright medium apple green, no secondary yellow.  Super nice stuff, great cutting, all priced at $800/ct.  I still have some of that stock, but not much, and my source is out.  The price, as I said, is the price of older stock, and unless one finds a good connection, Russian prices are now much higher.

Demantoid Garnet

Three Colors of Demantoids

And then that’s just what happened.  I finally met another demantoid seller with reasonable prices in Tucson!  I found Sergey’s booth tucked away in the back of JCK, he was sharing the booth with someone, and he had only Russian demantoids, nothing else.  Sergey has a geology degree and taught at the University of Moscow for a while, then – Russian economy being what it is - decided to try himself at gems selling instead.  And he was very knowledgeable about his stones.  His stock was all well cut, ranging from an olive green to a rich deep forest green – I think industry calls it “emerald green.”  Although there is dispute, sometimes “apple green” refers to the darker color, sometimes not.  There is agreement though that the top stones should be bright, they should pop, and they should not have any yellow in them.  After a long discussion with Sergey and louping many of the gems, I was convinced that the material was legit – it’s a little easier to judge demantoids because you can tell a lot just by louping them and looking at the inclusions.  So I took the risk and purchased some pieces.  I first showed them to my other source in Tucson, it’s not something one likes to do but I just needed to know I wasn’t making a mistake.  Then I took them to the lab in NY.  Josh Lents, my colored stone guy at GAL, loved the colors and he explained a lot to me about how to judge the gems.

Demantoid Garnet, Kenyan Tsavorite

Demantoid and Kenyan Tsavorite

It’s funny in a way: Russian demantoid is the only gem – that I know of anyway – that is bought because of its inclusions, not despite them.  Demantoid inclusions are actually made of asbestos – so don’t chew on them I guess!  The typical horsetail type inclusion is only found in Russia (actually I’ve heard conflicting reports about this, but that’s the official story).  Not all gems have them, the smaller the piece the less likely it is that it has a horsetail.  But some gems have partial horsetails, and others have asymmetrical whispy inclusions that are also quite distinct.  I’m including some photos here, please inquire if you are interested in purchasing them.  They are getting listed on Etsy as we speak.

Horsetail Inclusions of Demantoid in the Photo

Aside from the Ural mountains in Russia, demantoids (named after the French “demant” for diamond), are also found in Namibia and Iran.  Namibian material is considerably more olive in color, though it also has some nice dispersion.  Iranian material is quite rare, even rarer than Russian.  Some of it is also apple green. 

Whispy Inclusions of Asbestos

What about treatment?  Some Russian demantoids are heated at 800 F to enhance color (that is considered low heat), but this treatment is undetectable in the laboratory.  So the best shot you have at knowing if the gem was heated is to know and trust your source.  The treatment is permanent and stable.

You can find some photos of finished jewelry with these demantoids on the pricescope thread here.

And here's a video of one of our gems: 

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