Simply Marvelous Color

Color in tourmaline is a huge subject and I am only going to try and get a piece of it in this page.  I will not be defining terms and dealing with the rather esoteric world of color science.  I will try a talk about the colors and their settings in tourmaline gemstones that I personally have in the collection or have seen. One thing in the tourmaline world that I have found is the ever changing availability of different colors of tourmaline.  Some colors such as green, pink and blue are available all the time in some shades, but the rarer colors float in and off the market, so there is a need to act when you see something you really like in just the color and setting.  By setting I mean whether the color jumps out at you because of the structure of the tourmaline, the cutting of the gemstone or even the ambient lighting.  Believe me it really matters.

Pink/Red/Rubellite

The continuous range of color from the palest touch of pink to reds that are so dark that they are only transparent in smaller pieces, is one of the joys of tourmaline.  Where the line between red and pink should be drawn will always be a personal choice and I don’t think it is nearly as important in the trade as the distinction between pink sapphire and ruby.   Both pinks and reds can have purplish and brownish overtones that are displayed to varying degrees depending on the light.  Rubellite, a trade name for top grade red tourmaline, can have a purplish overtone, but never show a brownish overtone even in artificial light (yellowish light). (This definition is not universally followed in the industry where some dealers use rubellite for all levels of reddish color.)

Pink/red in tourmaline can certainly vary in darkness and the amount of purple or brown overtone depending on the angle you view the stone from, but I have never seen a completely different color in one axis verses the other.  I just alluded to an important presentation point with tourmaline that is often misstated or at least stated in a confusing manner.  That point is, tourmaline can only have two colors in any crystal that does not have zoning.   The blending or isolation of those two colors, by the cutting of the gemstone, makes up one of the reasons for the dynamic nature of color in tourmaline.  The only other color  complexity that I have seen with pink tourmaline is a distinct grayish shade in the axis perpendicular to the principle axis.

The reds tend to be both darker (This is particularly true with purple reds) and more included than the pinks.  There is only one notable exception to this guideline and Nigeria tends to produce all shades of red/pink in exceptionally clean crystals.  The darker stones tend to look both redder and are able to hide flaws better than pastel pinks.  There are rare examples in the collection where a red is both a solid red and not too dark to be very flashy.   These marvelous Rubellites generally depend on either zoning, or a significant difference in the darkness of the reddish color between the axis to be exceptional.  Pinks tend to be more included as they get hotter and also more fragile.   And I think that a top of the line hot pink tourmaline can be about as an intense a color experience as you will see in any gemstone’

There is one area of the pink/red world that has not been touched on here and that it is blending with orange. (I will leave the wonderful and rare suite of cuprian pink purples to the cuprian part of this page.)   The collection does not have a lot of richer red oranges, so I treasure all of them.   It does have quite a few peachy to melon colored gems that tend to shift between more or less red  to an orange (some of them may even be color changers) depending on the white light source.  I tend to think of them in the orange family because it is much harder to get fine quality oranges than pink reds.  I would say the orange reds have the same general display characteristics as pink reds over the full gamut of color intensity, from pastel to richly colored, but since I only have a limited number in the darker shades it is hard to be sure.

A hot, hot medium toned round with a few growth tubes.  #21 This standard round brilliant is a really hot pink that grabs the eye. It has good crystal and is eye clean except for a few growth tubes. It weighs 3.63 carats. This gemstone is a GEM and the best Rubellite in the collection, round. This is a special gemstone. It is a GEM, exceptional gemstone and I personally got it from a fine individual who has since passed away. It has a great medium tone and a well saturated color. It weighs 7.99 carats. and it is from Nigeria. Big Red from Nigeria, Darker toned Rubellite, oval. #292 This is a beautiful gemstone that is a personal friend. That is why I call him Big Red. He came from Nigeria and has that deposits eye clean nature along with fine crystal. Its medium dark plus tone level is flashy, but not eye candy. It weighs 9.98 carats. outragous, pure sweet pink eye candy, Barion cusion. #350 This is a radiating, uniformly vibrant pink GEM and the favorite stone of Jeff the photographer. It has everything a gemstones should have including a great size of 10.52 carats.

 

ORANGE/PEACH/DRAVITE

I love orange in tourmaline.  It was one of the colors I really wanted to get when I got back into faceting after a long hiatus.  You can approach it from either side, the red or yellow, and find all levels of tone and a wide variety of saturation levels.  I don’t know if the best orange in tourmaline is as good as some of the garnets, but color can transcend the brown cast of dravite.  The degree of dichroism can also vary widely in the oranges.

After reading about oil painting, I think I have a better sense of why oranges in tourmaline tend not to be as saturated as some gemstones.  I think it is because there is no single, color inducing, trace element or defect in tourmaline that produces orange.  In painting the brightest and most intense colors (highest chroma) are made from a single pigment and are consistently more expensive than blended colors.  So where does this leave tourmaline.  Well it needs to have high levels of at least two coloring agents in the right proportions.  That is not common in nature.

Radiation has been used to induce an orange color in tourmaline and some of it is stable.  I have read over and over again that irradiation caused permanent stable colors in tourmaline (this includes reds), but that is only partial true.  The yellow color that can be formed, along with a stronger pink from the oxidation of manganese in the crystal by radiation, is only stable as long as there is a crystal matrix that can accept the dislocated subatomic particles (protons or electrons).  (The crystal has to be without an electrical charge in the end.)  I think that this temporary instability in color is not seen as a problem because it is a rather brief period of time.  So by the time you get to see the gemstone it has a stable color.

One of the most interesting features of some of the orange tourmaline is its color shifting/changing to red/pink.   I had many times, while I was trying to post comments about the collection , where the pink/orange designation on the box did not match the color I was seeing.  I would check under my yellowish light and there would be the orange while the pink popped back in the rays of natural light.   All levels of tone are involved and I have seen next to nothing written about this property of tourmaline.

The collection has a tasty suite of melon colored tourmaline that are ripe with oranges that do not have the dark tones of brown.  This includes some fantastic pieces of pure melon along with blends of yellow and rust, all from Del Gado, a province of Mozambique.  Even Brazil is not left out, because I was able to recut a nice piece of “salad” (inexpensive included tourmaline that is native cut in Brazil) into a nice oval that is quite included, but hits the color spot.  Still these are exceptional oranges and most oranges you will see from Africa are either brownish or come toward orange from the yellow side.

Sunset tourmaline from Tanzania, brings mixed feeling out in me.  I finished a emerald cut that is over 10 carats and one of the larger pieces of rough I have ever seen in this variety, while having a small piece fall apart on me.  The large emerald cut has a fine orange amber color and is pure, but it was a real effort to polish.  Other golden oranges can be sensitive, but generally can be dealt with.  I just (2013) finished a round that has as bright an orange as I have seen from the c axis color, while showing a pretty pure golden yellow eye because of its orientation.  I had to recut the pavilion because of marking and the potential loss of the culet, but it is beautiful.  I think that the structural weakness of some richer oranges comes about because of the natural irradiation of the crystal.  It shares that trait with some hot pinks.  Not to make things too simple, the very large tri color that is on the welcoming page of this site, has a fine orange and it is very stable.

Finally we should look at traditional davites and how the browns caused by desaturated oranges can turn tourmaline exotic.  Dravite, whether they are derived from yellows or oranges or reds have never been highly prized in the trade.  They can be extremely dichroic to the point of having closed ends (a principle axis that does not transmit any light).  And brown has not really been an in color, but times change.  Diamonds on the verge of being industrial are given sweet names and declared to be desirable.  As usual lowly tourmaline can blow diamond away with its browns.  Most of them are from East Africa and are such bright exotic gemstones that dravite just doesn’t seem to cut it.   Names like earth tones, mahogany and  different spices have help tourmaline get a better audience and acceptance by the public.  I think the “new” dravites are great and the collection has quite a few.  I particularly like the rich orange browns that I call mahogany after my old woodworking days.  You may have wonder why I went gone completely brown in the orange section.  Well brown is not a spectral color and therefore depends on the mixing of colors to be produced.  So under many browns there lies an orange heart.

The next time you’re looking at tourmaline try an orange, I am sure you will fine it appealing.

Large, clean, brigh,t rich orange, emerald cut.  #541 This is a gem. It has everything a large 10.07 carat orange emerald should have. The orange is on the golden side depending on the light, but it counts it is orange. Big peach round with light pastel tone level. #500 This large peach oval is flawless. Its crystal is outstanding and well suited for the stone fine crystal. The oval is not dichroic and weighs 20.17 carats. This is a GEM with a great orange color that has a secret, round  #791 This large deep round is a bright,flashy, well saturate and vivid orange. The depth comes from having a split horizontal split mains on the back and a high crown. It also has twelve mains on pavilion and crown. The fantastic, medium tone level, orange comes from the blending of two colors. A rust color in the pavilion and a yellow color in the crown. You can see the bi color nature of the stone when you tilt it, but face up it is orange. It weigh 12.95 carats. A great caramel color in a nice Barion cushion cut.  #344 This mildly dichroic Barion cushion cut is eye candy to me. In fact it reminds me of caramel. The gemstone has a step cut crown which helps to make a bright gemstone. It appears to be eye clean and with fine crystal. It weighs 3.96 carats and I love it.

Bruce

Yellow, Golden Yellow, Dravite, Canary, Tsailisite

The evolution of nomenclature in tourmaline certainly indicates to me that there is something of value in a “good” name.  I have seen rubellite stretched into pinks and then declared that the name should be banished because it is deceptive.  Rubellite does not look like ruby most of the time.  It should, but that does not mean it should only be compared to top quality ruby.  I have  seen Indicolite stretched into blue green, to the point where blue just barely dominates the green.  Again the call has gone out to drop indicolite (indigolite) as deceptive etc. rather than limit a fine name to truly blue tourmaline.  Yes I know that it is rare, especially in the lower tone ranges and the whole cuprian/Paraiba world makes blues more complicated,  but I don’t see it as deceptive if properly defined and used.

Now the story with yellow is almost the opposite of rubellite and indicolite.  Before the opening up of East Africa, there was little call for naming a true yellow in tourmaline because Brazil, wonderful as it was, did not produce this color or at least not in any commercial amounts.  (It dominated the tourmaline market) I put the commercial part in to cover myself because the story of tourmaline/ Brazil and the wholesale trade in tourmaline that has been on going with Africa for years, makes it difficult to make a definitive statement.

So this has left dravite, a fine old name of a species of  tourmaline. to fill the bill for yellows that mainly had a lower saturation level and therefor are shaded by brown. Golden has always been popular for lightly toasted yellows and still has a place. Yellows with a greenish cast are much more common than purer yellow and after a round of now obsolete names were dropped by the trade, this range of colors should be called yellowish green/greenish yellow etc. Where does true yellow come in, the story is only beginning.

With the discovery of high manganese tourmaline in Madagascar, tsailisite was  proposed for a hypothetical (manganese tourmaline ) end member (mineral) as an addition to the tourmaline group.  Yellow was associated with the high manganese discovery (the name is based on an area in Madagascar that produced the tourmaline) and continues to be so, despite the fact that tsailisite, as proposed, has never been found.   (In a recent development Tsailisite has been discovered on Elba.) Tsailisite has gain wide acceptance despite vigorous calls from mineralogist to drop the name as obsolete.   I have never been sure what color boundaries, tsailisite the gem name has, but the pure yellows (advertised as tsailisite or not) that I have been able to get over the years are beautiful and highly prized by me.  It is one of the rarest colors of tourmaline, particularly in higher tone levels.

Now we come up to the recent past and a new era of color in tourmaline has been declared.   A discovery in East Africa has finally filled in the spectrum of colors in tourmaline with a true, brilliant, saturated yellow.  This declaration of uniqueness is remarkable considering that there already is a widely accepted name, tsailisite, for yellow without brown or green overtones.  But this is the Trade with a new item to sell and therefor a “good” name was hatched, Canary.  (If you want to read more about it, there is a wonderfully cute story being regurgitated on the web about it).  I have not seen this variety of tourmaline in person, but I am sure that it is beautiful.  Still, the use of “canary”  does not help the name game.

I started out this section on yellow in tourmaline with the need to restrict rubellite and indicolite to the top grade colors of red and blue in disagreement with those who would drop them completely.  With the announcement of canary tourmaline, the Trade has given tourmaline a new name for the ultimate in yellow tourmaline.   Will it be stretched to include lesser, more common colors in the future, who knows, but it does seem to fly in the face of the group that wants to drop all varietal names.

It looks like I have been waylaid by the name game again, but I will try and end by giving a brief overview of yellow in tourmaline.  Any yellow that has a significant amount of green or brown in its color is much more common that pure yellow.  I have found that many grades of paler, pastel tone levels of yellow  are not particularly valued.  Even pinks tend to be valued over peaches and pinks are much more common.  I personally love the wheat, ecru and beige etc. tourmalines, in the collection, because they are much rarer than peaches or pinks and I am rather a neutral kind of fellow at times.  Above all this lies the ethereal yellow gems that are probably included, but still stand out in their exceptional presence.   They deserve a “good” name that is restricted to the best.

A slightly included pastel yellow emerald cut.  #306 This smaller emerald cut has only a touch of an inclusion far from the table. It pastel tone yellow lacks the brown problem of many yellows, and makes the stone desirable. It weighs 2.29 carats. A most pleasant pastel with a medium tone level that is eye clean.  #691 This shield cut has a most pleasant pastel yellow that when combined with a medium tone level says, pure baby yellow. It is eye clean and has fine crystal. I love this 3.47 carat gemstone. Large, pastel yellow shield cut.  #895 I like this gemstone. It has everything going for it to be a great gemstone. The pastel yellow, with out a hint of green, shield cut has good size and a very clean transparent look. But the yellow does not have the vividness of my richer more saturated examples of yellow. It weighs 8.42 carats. The larger ecru colored round is a GEM and I call her Queen Ecru.  #692 Sometimes everything goes right and a GEM is produced. This modified round has twelve horizontally split mains on the pavilion and eight modified step cut mains on the crown. This great cut along with great transparency and a fine polish, produced a GEM even when the finished gem has a rather pale brownish yellowish orangish color (ecru). No stone is bright and flasher under a wider range of conditions. She weighs 11.69 carats. There is a light veil threw half the round, but its yellow color makes for a great gemstone.  #830 Pure vivid yellow color is prized in tourmaline. And this is one of best I have. It has a fine medium tone level and a yellow that not drift toward green. It is moderately included and this does affect its flash. Still it has plenty of punch to carry the great color. It weighs 1.91 carats.

Green tourmaline, Elbaite, Verdelite, Chrome tourmaline

When you begin to read about color in tourmaline, you run into endless disclaimers about the completeness of the article due to the complexity of the subject.  I can appreciate their insecurity, that many times come from just parroting other peoples work, but with the advent of commercial quantities of purple, yellow and orange from Africa, I don’t see any part of the color wheel that is missing.  And with green I will flatly say that I think it comes in every conceivable shade of green possible.  There are many different settings for the wonderful world of green tourmaline from strongly dichroic to none at all that can be seen by the eye and the mere wisp of color to a darkness that is profound.  Its principle competitors in nature gemstones are emerald, peridot and tsavorite.  In exceptional cases tourmaline can have the same color, if not the same presentation as its competitors.

Now green may be the most common color in tourmaline (red/pink would be its only challenger), but  its value and the availability of different shades varies greatly.  Yellowish greens are the most common and when clouded with brown because they are not well saturated, are not very desirable.  (It has been determined that titanium causes the brownish overtones in green tourmaline.)  But when the ends are open and the color vivid and fully saturated, yellowish green, with its normally eye clean, high quality crystal, can be outstanding.  It is the prevalence of this range of color in tourmaline that lead the Trade to use the mineral name Elbaite (the most common species of tourmaline in gemstones) for yellowish green tourmaline.

Blue green tourmaline tends to be treated separately because of where it is found and its completely different price structure.  Different gem pockets in a pegmatite can produce wildly different colors. but if you have blue, green will be intimately associated with it in tourmaline, because iron produces (along with copper that is discussed later) both colors with relatively little change in its chemistry. ( Titanium is also a factor in coloring the full range of green tourmaline.).  Dichroism  can be very strong in blue green tourmaline and many pieces of crystal are cut in emerald cuts to minimize the impact of closed ends, (lack of transparency down the c axis).  Still other blue green tourmalines do not show any dichroism.  This is especially true in the light toned, more aquamarine like gemstones.  As far as competitors go, there really are very few that can compare with a fine, rich, blue green tourmaline.  Many sapphire have a greenish axis, but the presentation of green in sapphire is generally minimized.  Green shades are  just not sapphire/corundum’s best effort.  Topaz does produce a blue green color, but naturally color material is so rare that it should probably be placed in with blue green diamonds as a object for the collector.  Finally we should look at beryl, the mineral parent for both emerald and aquamarine.  There is also a variety called green beryl (it is colored by iron rather than chrome or vanadium in emerald).  Out side of emerald, which can have a distinct bluish cast, all blue green beryls are heated to remove as much of the greenish shade in the bluish stones (aquamarine) as possible.  Recently there has been more interest in bluish green beryl, but the demand for that wonderful aquamarine blue keeps the heaters busy).  Green beryl can be mistaken for pale emerald, but is limited to lightly toned material that would be heated to bluer aquamarine if it could be, in  my opinion.

Heat is routinely applied to blue green tourmaline from some locations such as Namibia to lighten the tourmaline’s color.  I was surprised to find out that even rough is heated before faceting.  This generally increases the probability of breakage, by not having the surface flaws removed first.  I usually say that I don’t think that most of my collection has been heat treated because I cut rough that has not been prepared for heating and I don’t heat anything.  But in the case of Namibian blue, which usually has at least a bit of green,  I can not be sure about heat treatment.  I have found them to be prone to spontaneous cracking that moves ahead of the grinding and can destroy a stone.  This maybe an indication of heating the rough.

Summing up blue green tourmaline in a single sentences is difficult.  It can be very pale or dense with completely dark ends.  I can be rather dull or full of vigor.  But if you want a bright, rich, blue green gemstone, there will be a significant price to pay for a fine tourmaline, but it is the only realistic choice on the market today, in my opinion.

Excellent apple green non-dichroic oval, Mozambique This is a beautiful gemstones. It has a great medium toned apple green color. It appears to be eye clean and is bright and flashy. It weighs 9.36 carats and came from Mozambique. A bit toned down yellow with a wash of green, round.  #91 This standard round brilliant is a rather mild yellow with a wash of green. It appears to be eye clean and has fine crystal. Its larger size of 6.10 carats supports a medium tone level in this flashy gemstone. . Large Barion Cushion cut, dichroic green. #349 The Barion cushion cut mixes the two dichroic colors of green beautifully. The gemstone appears to be eye clean and with great crystal. Its completely open and moderately toned body weighs 23.64 carats. Darker iniform green oval with bright flash.  #894 This darker green oval does not appear to be significantly dichroic. It has sharp green flash, but there are darker factors in its tone value. It weighs 2.81 carats. Larg, long ratio, clean classic tourmaline green emerald cut.  #761 This large emerald cut has darker ends, but a truly great medium toned tourmaline green middle. The well saturated green flashes well and has great transparency. This pure, normally cut, emerald cut weighs 12.3 carats. Glorius bright emerald green color, chrome tourmaline. #485 This is a GEM. This chrome green tourmaline has an ideal tone value and great flash. Its saturation level is very high and it weighs 2.67 carats. A large bright non dichroic mint green round.  #936 I like this gemstone. Its medium pale tone value and mint color make the deep gemstone a real flasher. Its deep cut is a combination of spit horizontal mains on the pavilion and a modified step cut on the crown. It has excellent crystal, is eye clean and weighs 14.37 carats. Top, top quality glowing sea foam, Barion cushion cut.  #597 This is a gem. It has everything going for it including a really fine glow. It is only mildly dichroic and its color is dominated by the stronger c axis color of yellowish green. It has a medium tone value in a flawless heart. It weighs12.47 carats.

 

 

 

Blue, Indicolite, Indigolite, Color Change Blue to Green

I have been trying to get a more rounded picture of the present state of the search for blue tourmaline from the inter net since my personal experience is limited to mostly Namibia and Mozambique cuprian tourmaline.  A spectral color like “Blue” without any overtone is an ideal that is not attained in the real world of gemstones.  I have never seen really fine blue tourmaline from Brazil, but the principle problem with Namibian blues is not the purity of blue, in the best examples, but their dark tone level and their inclination to shift to blue green in incandescent/yellowish light.  I have found lower levels of tone and more gray/green in gemstones, that I think may have come from other areas of Africa, but it is very hard to get reliable source locations.  Afghan is represented in the collection by one exceptional indicolite that unfortunately suffers from a small amount of reduced transparency down the c axis and a bevy of pale blues. I will not be discussing cuprian tourmaline on this page since true blue is not in that world and cuprian tourmaline deserves it own page.  On that page I will be also be discussing blue/purples since I have only found blue purples in tourmaline with copper as a chromophore.  I have seen price lists as a guide for cut violetish blue tourmaline, but I have not seen a genuine opportunity to buy rough.

Gray is a composite color and as such, you will not find it on the color wheel because it is not part of the spectrum.  The lack of color saturation that causes grays certainly impacts blue tourmaline, but I find it more of a problem with light to moderate tone gemstones than the blues that naturally have a darker than desirable tone level.  It is the playing with green that keeps most blue based tourmaline from qualifying as Indicolites/blue tourmalines.  While writing posts for this site, I was surprised to find many “blue” tourmalines that I believe came from Namibia , not only shifted toward green, but went the whole way to green under incandescent light.  And a fine green at that.  Still a significant percentage of my blues stayed blue in both natural and incandescent light.  And as a lover and collector of tourmaline I truly treasured the stable blue’s, but I am not sure the Trade values them more highly than slightly greenish blue, when the tourmaline’s color has the same fine setting (brightness, cleanliness etc.)  One element of setting that I must discuss with greens to blues is dichroism.  It is an especial strong part of the picture with these colors and can lead to dark ends from lack of transparency down the principle axis.  You can minimize the darkness with emerald cuts and steep ends, but you can not eliminate it.  Excessive dichroism is NOT a problem with all blue tourmalines (which comes in every conceivable tone level) and I have gemstones with a wide range of tone values that do not appear to be dichroic at all.  But this is much rarer in darkly toned blue to green tourmalines.

A fine medium pastel blue color without a hint of green, but with a touch of gray, oval.  #809 This is a fine Indicolite, blue tourmaline. It has everything going for it in a medium pastel stone. It is not dichroic or bother by a greenish side. It does have a touch of gray and weighs 4.05 carats. Included, but a great saturated blue color round. #131 This standard round brilliant.can get attention, even with its medium dark tone value, because of its well saturated blue color. Its inclusions are a fine web of rather evenly spaced flaws. It weighs 3.64 carats and is a beautiful gemstone. A bright dichroic emerald cut, GEM, from Namibia  #397 This is an outstanding gemstone. It has a bright blue color that is significantly darker tone in the ends, than the sides of this GEM. It has a good size at 5.27 carats. Excellent completely open blue to blue green emerald cut Namibia.  #398 This is a beautiful gemstone. Its medium rich toned blue does slide into blue green in yellowish light, but is still a blue. It is not dichroic at all and very flashy for an emerald cut. It weighs a nice 3.86 carats. An excellent gemstone with great medium toned blue green color, emerald cut.  #395 This is a beautiful gemstone. It has a great medium toned, completely open, non dichroic body. No problems with flash or flaws and a great crystal. An all around great gemstone that weighs 5.22 carats.

 

Purple, Siberite

Purple in tourmaline is an elusive color in tourmaline.  It was one of the colors I wanted to focus on when I started cutting again after a long hiatus.  The discovery of cuprian tourmaline in Mozambique and my ability to get unheated material both before it was discovered in gemstones I sent the GIA and after, permitted me to complete the color wheel with purples and purple blues.  My search for blue purples to purples that are not cuprian has been pretty fruitless.  I did get some grayed medium toned purples from Madagascar and at least one them is a pretty decent stone, but they are not well saturated.  I have seen non cuprian purples from other locations on the web, but never in person or been able to purchase any rough.

It is not difficult to get pinks and reds that have a purplish cast.  Generally the purple pinks are not valued above comparable pinks.  I have also found that purple pinks tend to have transparency problems and just do not flash like good quality pinks.  The one situation where a purplish cast in a red is praised is “siberite”.  It was a name given to high quality red that had a strong purplish cast and came from Siberia.  I have never seen any of it in person, but this is what I have put together from reading.  Today I think most dealers would call the material a rubellite with a strong purple cast.  I have this type of tourmaline in the collection and I have also seen a couple of my best reds turn purple under bluish natural light, much to my chagrin.  Still none of red purple family really gets to be a strong saturated purple like copper and manganese can produce.  I will keep looking.

Big purple GEM, deep 12 main round.  #291 This is one of the great cuprian stones in the collection. It is eye clean and with fine crystal. Its color, blue purple, is its most outstanding attribute and along with great clarity makes it a first class GEM. It weighs 16.66 carats. An included and sleepy purple that still pleases, oval #130 I am addicted to cuprian purple. This oval came from a very included piece of rough, and it is a passable gemstone if you love purple with a touch of blue, a rare color in tourmaline, It weighs 1.97 carats. Long ratio maroon colored emerald cut. #501 Nice, medium toned, mildly dichroic, maroon emerald cut. It appears to be eye clean and with fine crystal. It has a bit of chipping on the keel and weighs 2.14 carats. Included, medium light pastel purple that is not cuprian.  #825 This is one of my best purples that does not contain copper. It has a medium light tone value with a bit of gray. Still its saturate is much better than most non cuprian purples. This emerald cut is included with a white non reflective inclusion in one corner. It weighs 1.62 carats.

Only four purples, the first two are cuprian and the last two are non cuprian purples.  More purples under cuprian.

One final note before I wrap up this page with an overview of cuprian tourmaline and its colors.  I have read that tourmaline’s are best seen under natural light and I have gemstones that certainly would agree with that.  But the complex nature of color, in all its levels of tone, makes such a generalized statement impossible.   I strongly recommend that you study any tourmaline under a wide range of lighting conditions to see how the gemstone responds.  Beauty in color is very personal and a higher price will not always get you a prettier gemstone in your eyes.

Cuprian tourmaline, Paraiba, paraiba like, paraiba type, copper bearing

I am including this section of a page on color and its varieties in tourmaline as an example of a failed attempt to define color by chemistry in tourmaline.  Paraiba tourmaline is a wonderful world of beauty and some of its colors are probably unique to a mixture of copper and manganese chromophores.   But the most important and expensive Paraiba have a color range between cyan and green that is NOT unique to Paraiba or any of the cuprian tourmaline found in other locations.  Iron, that wonderful traditional chromophore in tourmaline, can produce all the shades of color that copper can produce by itself, in tourmaline.  So does this mean that the Paraiba “effect” of great praise and high prices, just a marketing ploy?  No, there are other factors in the greatness of Paraiba that transcends color, one of which is the contentious property of “neon/glow”.  This property, of appearing to generate light in excess to that which the eye/mind expects to see reflected from the gemstone, is essential to the beauty of Paraiba.  Unfortunately, not all tourmaline with the proper provenance, color and chemical make up have that neon glow.

As you can see the nomenclature of copper bearing tourmaline that came from Paraiba and now other sites in the world is complex.  I discuss it in more detail other places on this site, but I wanted to introduce you to a set of wonderful colors that I have only truly seen in copper bearing tourmaline, vibrant blue purples.  As I have stated before, blue purple has been the hardest part of the color wheel for me to obtain in tourmaline.  It still is not easy and it is sad to me when beautiful unique blue purples are heated to produce cyan to green gems that have colors that are far less interesting to me and the world of color in tourmaline.  The heating reduces the oxidation level of the manganese in the tourmaline and basically eliminates the red factor in the naturally purplish tourmaline.

Big purple GEM, deep 12 main round.  #291 This is one of the great cuprian stones in the collection. It is eye clean and with fine crystal. Its color, blue purple, is its most outstanding attribute and along with great clarity makes it a first class GEM. It weighs 16.66 carats. An included and sleepy purple that still pleases, oval #130 I am addicted to cuprian purple. This oval came from a very included piece of rough, and it is a passable gemstone if you love purple with a touch of blue, a rare color in tourmaline, It weighs 1.97 carats. Included cuprian oval with mixed blue/purple/pink color.  #592 Under the lop, you can see flaws in this interesting cuprian gemstone that must have been filled with a fluid that changed the surrounding volume of stone to purple from blue. There are also pink areas mixed in with the blue and purple,areas in this moderately included gemstone. The inclusions do effect the flash of this moderately toned stone that weighs 2.30 carats. Excellent, medium light, slightly included, pastel lavander round.  #271 This is a beautiful standard round brilliant in a truly rare, well saturated, pastel lavender. It is cuprian and is slightly included. It has a fine medium tone level and weighs 2.68 carats. Eye clean, deep pavilion, lavender round.  #31 This is a beautiful gemstone in a very rare color for tourmaline. Its well saturated lavender color comes from copper and manganese. It is eye clean and has fine crystal. It weighs 6.35 carats. An eye clean, with great crystal, medium pink, deep round. Cuprian This round with horizontally split mains is eye clean and with fine crystal. Its color is a very nice, but not particularly hot, pink. It is cuprian and comes from Mozambique. It weighs 18.68 carats. Large bright cyan blue, cuprian, pear shaped GEM.  #941 This cuprian tourmaline has a fine medium toned body with plenty of flash. It is a pure cyan color without dichroism. It is eye clean and the only pear shaped gemstone in the collection. It weighs 13.90 carats and is a GEM. Rich, intense, cuprian bicolor of cyan and emerald green round.  #942 This is a GEM. It has everything a great cuprian gemstone should have. It has vivid intense cyan and emerald green colors. The green color is in the culet with the cyan in the crown. The stone has a split main pavilion and a high crown. it is both eye clean and with great crystal. It can not get much better than this and it weighs 4.54 carats. Laurellite, cuprian, blue purple oval from Mozambique.  Included. This oval is very large at 27.13 carats. It is significantly included, but still has good brightness and flash for a moderately toned gem. Its color changes from purple to blue which is defining for Laurellite. High grade Laurellite, flawless and medium toned. This is one of the original Laurellites that I sent to the GIA to be tested. It is without problems and is my best Lauellite, a name I use for cuprian tourmaline that has a reverse alexandrite color change. It weighs about 5 carats. Included, Very Bright, Non Dichroic, Medim Toned, Green, Round.  #148 This standard round brilliant has an exceptionally bright medium green color. It is included, but they are really overwhelm by the beauty of this gemstone. It weighs 6.03 carats. Cuprian. Exceptional yellow green copper bearing round.  #62 This standard round brilliant is a GEM,(exceptional gemstone) with a "neon" look that may come from its copper content. It is eye clean and has great crystal. It weighs 3.17 carats.

 

Bruce

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