shape
carat
color
clarity

Peridot: Price discrepancy? Color Change Garnets: Value?

RedSpinel

Shiny_Rock
Joined
Apr 28, 2012
Messages
211
***First topic: Peridot......

I remember hearing and reading that Arizona Peridot were nice, but cheap. On the other hand, I saw that Pakistani Peridot was often very expensive(for peridot). So early on I bought some little .5ct AZ Peridot for like $3 apiece. Then I bought a matching pair of 2 AZ Peridot(1.7ct apiece rounds) for about $20. Later, I won an auction on Ebay from Thailand for a Burmese Peridot of 3+ct for about $45. All of these 3 stones are clean, well cut and have the stereotypical apple-green Peridot color.

So then I'm looking at a UK Ebay dealer's store, and he is selling Pyang Huang Peridot on regular auction starting at only about $9 or so, and the stones are around 2.7ct - 4ct and they some were up to about $60 on auction with hours to go. At the same time, he also had Mogok Peridot that WAS NOT on auction and had a "buy now" price of $599 - $799 for 4ct - 5ct stones. The odd thing was, that all the stones were well cut, very clean, and they all had the exact same color, regardless of whether they were Pyang Huang(wherever that is), or Mogok(Burma). The color was more lime green and maybe a tiny bit less apple green than usual for Peridot, but still the Pyang ones were just as nice as the Mogok ones, so why the HUGE price discrepancy? Besides, I thought Pakistan was the "Mecca" of Peridots, not Mogok! :confused:


***2nd Topic: Color Change Garnets......

For a few years, I would occasionally see these color change garnets that supposedly went from blue to raspberry red depending upon the light source, but they were usually small, and usually very included, and usually expensive. But I finally bought 2 of these blue-red CC Garnets. Then came the disappointment..... On the sales pictures of the stones, they clearly went from blue to raspberry red, but when I got them home and tried them under many different lights(sun, fluorescent, incandescent, flashlight, etc), but I could not get them to go red OR blue! So I sent both of them back for refunds! I paid over $125 for one of them that was only 1ct too! I keep seeing these things, but I dont know what light they are using, only that it must be some unusual, uncommon light that if you wore the stone, you'd never run into that light, so the garnet would never be either red or blue! :cry:

Now. before I bought those 2 tiny, overpriced stones, I bought another CC garnet that has a different color change. It is a Marquise cut 2.8 ct stone, that changes from a pretty raspberry pink to a bright, shiny metallic copper brown. It is a HUGE change in color, and it does so under normal light, either fluorescent or incandescent. Also it is either raspberry pink in sunlight or copper brown in sunlight, I dont remember which. Its a very clean, well cut stone, no eye visible inclusions. I love it, and it always gets oooohs and aaahs when I show it to people under those different lights. I got it from a reputable dealer on auction for about $75.

So my question is, whats the deal with the red-blue color change garnets, are they for real? What possible light source do you have to go and find in order to actually get them to change from red to blue? It seems to me that if they arent common lights, then it kinda defeats the purpose of even having them if they are some ugly greyish brown most of the time!

Secondly, how much would a stone like mine, which I described above be valued at roughly? I have no idea what the value of a 2.8ct CC garnet is worth. Obviously the color is important.... I dont plan on selling it....
 
I quickly photographed this one out of my personal collection in mixed light. Standard daylight-equivalent fluorescent on one side, and Reveal incandescent on the other side. Nothing special at all. :) I walk outside and it's dark blue like a sapphire. I walk indoors under my kitchen "can lights" and its bright pink. 1 carat is a decent size for the red-to-blue color-changers, I wouldnt call your former 1ct stone tiny. ;) Mine feels bad- it's 1.28. lol



The other CC garnet you have sounds like the stones coming out of Kenya. They aren't extremely rare- though I've heard rumors of the supply running out already, or is expected to very very soon. But they aren't priced very much higher than a nice quality pink/purple Rhodolite (precision cut). Last time I checked, prices for the cleanest stones with a nice copper-to-cherry red color change were priced a bit above 100$/ct. (precision cut) I could be off on that now for current market, so take it with a grain of salt.

Cant really help you on the peridot. I dont know too much about it. But i'll bet the price discrepancy has to do with the supply from specific location and/or premium of location similar to the premium on Burmese stones vs. Vietnamese/Madagascan/Sri Lankan...

P3280452.JPG
 
It used to be thought that you could get garnets in most colours except blue. Then blue was found in Bekilly! However the majority of blue colour change garnets are, in reality, a green/blue. There are very few BLUE garnets but they DO exist. Typically they are on the small side (around the 1ct mark) but there are larger ones. The clarity can suffer on some of the bigger stones. However, to get a great blue/pink you'll be lucky to find one that is relatively expensive. The blues are sought after and therefore you pay for what you get. The colour change (irrespective of colour ways) can be weak to strong and anywhere in between.

Colour change garnets in colour ways other than green to red and blue to pink/red are not too expensive and some have a phenomenal change/shift. I have brown to red, champagne to pink, pink to purple, green to red etc etc!

So basically, if you get a blue one with a good colour change, expect to pay a fair amount for it!

As for Peridot - if all the photos have the same colour in the auctions, have your checked the vendor's feedback? Do you think the photos could be manipulated?
 
Stonebender|1335825988|3184351 said:
I quickly photographed this one out of my personal collection in mixed light. Standard daylight-equivalent fluorescent on one side, and Reveal incandescent on the other side. Nothing special at all. :) I walk outside and it's dark blue like a sapphire. I walk indoors under my kitchen "can lights" and its bright pink. 1 carat is a decent size for the red-to-blue color-changers, I wouldnt call your former 1ct stone tiny. ;) Mine feels bad- it's 1.28. lol



The other CC garnet you have sounds like the stones coming out of Kenya. They aren't extremely rare- though I've heard rumors of the supply running out already, or is expected to very very soon. But they aren't priced very much higher than a nice quality pink/purple Rhodolite (precision cut). Last time I checked, prices for the cleanest stones with a nice copper-to-cherry red color change were priced a bit above 100$/ct. (precision cut) I could be off on that now for current market, so take it with a grain of salt.

Cant really help you on the peridot. I dont know too much about it. But i'll bet the price discrepancy has to do with the supply from specific location and/or premium of location similar to the premium on Burmese stones vs. Vietnamese/Madagascan/Sri Lankan...


^^See, thats what I was hoping either one of the 2 stones I bought(at different times) would end up looking like. Most of the ones I see for sale are actually under 1ct. I've seen them down to .2 cts. But in the pics, they will look red to blue, but when I got each of the 2 I bought home, they werent blue or red. They were dull, ugly colored. One was about 1ct, the other wasnt much more than .7cts.

You apparently got lucky with that one!^ Thats obviously both blue and reddish.

**3 questions: How much did it cost? How clean is it? Where the heck did you find it?
 
LD|1335828913|3184388 said:
It used to be thought that you could get garnets in most colours except blue. Then blue was found in Bekilly! However the majority of blue colour change garnets are, in reality, a green/blue. There are very few BLUE garnets but they DO exist. Typically they are on the small side (around the 1ct mark) but there are larger ones. The clarity can suffer on some of the bigger stones. However, to get a great blue/pink you'll be lucky to find one that is relatively expensive. The blues are sought after and therefore you pay for what you get. The colour change (irrespective of colour ways) can be weak to strong and anywhere in between.

Colour change garnets in colour ways other than green to red and blue to pink/red are not too expensive and some have a phenomenal change/shift. I have brown to red, champagne to pink, pink to purple, green to red etc etc!

So basically, if you get a blue one with a good colour change, expect to pay a fair amount for it!

As for Peridot - if all the photos have the same colour in the auctions, have your checked the vendor's feedback? Do you think the photos could be manipulated?


Yeah, I saw a garnet advertised on the internet about about a year ago, and it was supposedly a real, pure blue garnet, and not a color change garnet. The picture seemed to validate that claim, but it wasnt all that bright and pretty though.

With the red-blue color change garnets, you seem to get the same types of similar inclusions consistently with them, and I dont really remember seeing those same types of inclusions in other types of garnets very often.

You have a green-red garnet? I havent seen that yet!

As far as your question as to whether the Ebay dealer selling Peridot might have "doctored" the pictures of the different Peridots from different regions, that explains why the blue-red garnets I bought looked different when I got them home, and could be the case with the Peridots too. The guy's Ebay rating was in the upper 98-99% range, but I often take that with a grain of salt, because it seems that almost everyone on Ebay has a rating in the upper 90% range! Even the worst, cheapest Thai gem sellers on Ebay have ratings that are 97-98%.... I think that as long as people receive their goods, they usually leave a positive rating, because it goes both ways. If I sell you something lousy on Ebay, and you give me a bad rating, I can turn around and give you a bad rating too! I think that reality often kind of intimidates people into just giving in and leaving good ratings. Not only that, if they sell you something you didnt like, and you return it, you are then supposed to give them a good rating anyway after you get your money back, so .....Grain of salt!

But most Peridots have the same color, probably more so than most other gems if you think about it. Its either apple green, or more of a lime green, and I think the more lime green ones are the more sought after and expensive ones. Thats what I had read anyway. That seemed to be supported when I'd see Pakistani Peridot selling for $150 per ct, and it had a more lime green, or non apple green color.

But again, most Peridot come in either of those 2 hues, so to see 6-7of them in pictures of all the same color didnt strike me as being all that uncommon, I just didnt understand why the price was so different. I just saw those on Ebay about 4 days ago, and they were listed as "Pyang Guang" Peridot.

Here's the item number: Item number: 290701106636

There you can look at that particular one and the Mogok ones. There might be ever so slight differences between 1 or 2 of them, but overwhelmingly they look the same as far as color is concerned.
 
I've seen red-blue CC garnets down to .10ct! And I've seen them sell! This is the second one of these I've bought. The first, my sister has and I bought it in 2004. I was just getting into stones then. Boy I got a deal back then! It's lovely with a perfect, medium to medium-light saturation. Great pink to blue colors. If I had known the value would increase as much as they have, I would have bought every one I could get. But.. oh well.

This newer one is med-dark but the colors are still obvious in normal lighting conditions. Eyeclean at 10x too!


There's even a red to intense purple-pink color change garnet too.
 
Peridot

The reason for the price difference between peridot from one locale to another? The answer is the same as why there is a price difference between a ruby from Mogok and from Mong Hsu, or a sapphire from Kashmir and from Madagascar, and etc. It is the name and perceived quality.

The second thing that comes to play now is that these stones you are looking at comes from different vendors. Each one has their profit margin to keep their business going (advertising, overhead, online costs, etc). Some vendors also play around with photography (photoshopping, bright or dim lighting situated to make the stone look their best), background colour could be neutral for accurate stone colour or a dark/black background to improve the perceived saturation of the peridot.

I have seen the Burmese peridots going for more money consistently than Pakistani peridots. Part of it due to the infamous fine chrome green colouration but again, this is a generalization. I am sure there are both good quality and poor quality peridots mined from the same location.

CC Garnet

The problem with CC garnets (like other gemstones) is photoshopping. Many of these have poor colour change or are too dark in tone. I have a 1 carat-ish pear than changes from greenish blue to purplish red but it is medium to medium dark tone. I have another 1 carat-ish cushion that is green to purplish red that is lighter in tone but the saturation isn't as good as the pear cc garnet. No special lighting is required to see the change other than the sun outdoors (blue or green) to indoors (fluoro or incandescent to bring out the purple/red side).

The quality of cc garnets isn't only the colour they show but the strength of the change. If the change is weak, then the colour becomes muddy in appearance. Other hues of colour change exist but are more common (and less expensive) and the trade desired blue to red colour change. The blue to red colouration are often from Bekily and the copper to red colouration are often from Africa.

Pricing of these types of stone has gone up significantly. I paid around $100 for mine many years ago (might be 2004 or 2005) and have not kept up with pricing. If you do a search on Multicolour, you will get today's pricing. They have a good selection of cc garnets with various changes (blue to red, the yellow or copper changes, etc).
 
I have a green-red cc garnet (bought it out in Sri Lanka from one of the local dealers ... it's 0.68ct and it was not cheap at all. That said, the clarity is good and the colour-change first class (I have not tried to photograph it though). Saw some nice green-red alex at the same time - but all under 0.25ct.

Also have a bluish purple to raspberry cc garnet that I bought a few years ago. It was a loss-leader for an online company and has a surface reaching fracture on the pavillion so it was cheap. I don't set my stones so the fracture was only an issue as far as cost was concerned. The colour-change is very apparent - a greyish blue-purple in daylight and bright raspberry in incandescent.

On the whole I think many people are disappointed by colour-change stones as they expect a more dramatic change than you generally get, they also expect both colours to be very nice - ie an emerald green to a ruby red (disney versions of each colour) and that just isn't going to happen.

Peridot prices are all over the shop - not sure why other than because you can and the name attached to the location. I'm not a big fan of peridot - it's my birthstone and the only stone that I have consistently broken (in fact the only variety I have EVER broken!)
 
Here's a small pair of cc garnets with a pretty fair representation of the color change you can expect to see:

http://www.etsy.com/listing/97122491/4mm-round-color-change-garnet-matched?ga_search_query=garnet&ga_search_type=user_shop_ttt_id_5621008

and here is a pair I bought on ebay (and returned). The color change was cool, but the stones were so dark... and small and expensive.

[URL='https://www.pricescope.com/community/threads/vendor-pictures-and-owner-pictures-of-ps-stones.109420/page-13']https://www.pricescope.com/community/threads/vendor-pictures-and-owner-pictures-of-ps-stones.109420/page-13[/URL]

(scroll over half way down the page) I have to admit i did edit the photos in order to show the blue color. It was impossible to capture (and darker than the photos show, if I remember correctly). It was a teal kind of bluish color.
 
GemFever|1335886917|3184799 said:
Here's a small pair of cc garnets with a pretty fair representation of the color change you can expect to see:

http://www.etsy.com/listing/97122491/4mm-round-color-change-garnet-matched?ga_search_query=garnet&ga_search_type=user_shop_ttt_id_5621008

and here is a pair I bought on ebay (and returned). The color change was cool, but the stones were so dark... and small and expensive.

[URL='https://www.pricescope.com/community/threads/vendor-pictures-and-owner-pictures-of-ps-stones.109420/page-13']https://www.pricescope.com/community/threads/vendor-pictures-and-owner-pictures-of-ps-stones.109420/page-13[/URL]

(scroll over half way down the page) I have to admit i did edit the photos in order to show the blue color. It was impossible to capture (and darker than the photos show, if I remember correctly). It was a teal kind of bluish color.



Wow! On that 1st link, they are asking $160 for 2 CC garnets that each weight only about .4cts, and are only 4mm across. Thats high! If it was one stone at or slightly over 1ct, then they'd probably want $300-$400 for it. They would be OK in a collection, but mounted in earrings as a pair, they'd just be too small to see clearly... Garnets are dense stones, so you dont get much stone for your money with garnets.

The CC garnets in the 2nd link dont look 2 bad. The cc is nice, but maybe they are a little dark, but the blue is nice. But thats the typical inclusion that I keep seeing in these bluish-reddish color change garnets. They often have those lines through them. I dont see that in many other types of garnets. What size was the CC garnet in link #2, and how much was the vendor asking for it?
 
Hm, let me pull up my ebay purchase history... ok, got it

the trillion was .52 at $100, and the oval was .74 at $120.

I agree that that small pair is too small to make effective earrings... I'd probably save my money and buy a larger stone. But I think it is a good example of the colors, and the type of color change you can expect.
 
I'm not sure I'd describe those as colour-change - for me they are colour shift. The blue is nice though.
 
GemFever|1335900220|3184948 said:
Hm, let me pull up my ebay purchase history... ok, got it

the trillion was .52 at $100, and the oval was .74 at $120.

I agree that that small pair is too small to make effective earrings... I'd probably save my money and buy a larger stone. But I think it is a good example of the colors, and the type of color change you can expect.



Yeah, ideally, we could all afford 4ct perfect red to blue color change garnets, but thats probably not reality, so if your getting a stone or stones for a collection, and you just need them as an example of what that particular stone looks like as a top quality specimen, than it makes more sense to buy a smaller, nicer one than a larger, uglier one. If they dont really need to be mounted in earrings, then their size should be good enough to sport in a collection.

But they dont show those 2 stones in link #1 under different light, so Pandora's probably right that they are color shift, instead of color change. But who knows, maybe under different light they might change to pink, violet or red, or some conglomeration of the 3!

But what I'm really curious about is how much a good quality color change garnet would appraise for? When you read almost any gem book and their descriptions of different stones, they dont mention color change garnets as being extremely valuable, yet people often charge lots of money for them, especially if they are fairly large stones, or even smaller stones!

I just wonder if AGL or any other big gemstone appraiser would put a large value on a good quality 1ct color change garnet? You see high dollar appraisals on rubies, sapphires, emeralds, but I wonder if they'd put a $1000 value on a 1ct top quality CC garnet? Not that gem appraisals are an extremely accurate assessment of the actual value of a gem. Usually you wont get as much as your appraisal says your stone is worth.

It seems that some times the values of these 'secondary' gems, as they are often called, are artificially inflated by a bunch of dealers, as different stones become "fads", then sometimes they drop in value as the fad ends.
 
Red Spinel,

In the last picture of the Etsy seller, you can see that the stones are purple. That's the color shift (I'd have to agree with Pandora, it's not really a change but a shift). That's what my ebay stones did too -- they went from teal to purple. Not to pink, I haven't seen that in real life yet.

I wouldn't feel comfortable commenting on the price. My personal philosophy is that outside of fine sapphires, rubies, and emeralds, all other colored stones are precious in my eyes only and not as items that can be sold. So the price I am willing to pay for them is based on how much I just *have to have* them. As for sellers inflating the prices... I'm not so sure. There are "fads" to be sure, but I think they are controlled by the market. It depends on supply/demand, what stones celebrities are sporting (there's been much talk of how the royal wedding made sapphires uber popular), etc... but that's just my two cents. Maybe our experts here can comment.
 
Here are some very bad photos of my blue/purple to red... neither shows the change at it's best (the blue/purple goes more grey and haas no pink, and the red is a very good raspberry) but you can get an idea: daylight top, incandescent bottom. (neither are photoshopped in any way)

pancolourchangegarnet1c.jpg

pancolourchangegarnet2b.jpg
 
Is it just me or that often, the purplish red (raspberry) side of the cc garnet has better saturation than tbe greenish blue (or blue) colouration?
 
GemFever|1335924880|3185287 said:
Red Spinel,

In the last picture of the Etsy seller, you can see that the stones are purple. That's the color shift (I'd have to agree with Pandora, it's not really a change but a shift). That's what my ebay stones did too -- they went from teal to purple. Not to pink, I haven't seen that in real life yet.

I wouldn't feel comfortable commenting on the price. My personal philosophy is that outside of fine sapphires, rubies, and emeralds, all other colored stones are precious in my eyes only and not as items that can be sold. So the price I am willing to pay for them is based on how much I just *have to have* them. As for sellers inflating the prices... I'm not so sure. There are "fads" to be sure, but I think they are controlled by the market. It depends on supply/demand, what stones celebrities are sporting (there's been much talk of how the royal wedding made sapphires uber popular), etc... but that's just my two cents. Maybe our experts here can comment.



I was just curious how much that particular dealer was charging for that grade of CC garnet as opposed to how much other dealers are charging, and as a gauge on market prices right now, but I completely understand your discomfort at mentioning the seller's asking price, and I too have paid more than I probably should have for certain stones, simply because I wanted that particular stone a lot! I try not to do that too often though.

What I meant about price fluctuation due to gem "fads" is what you see on the jewelery networks. They will introduce some supposedly 'new' gemstone to their audience, then pump up that gem stone from day to day, while telling everyone that the mine is running dry, and you MUST buy now! But sometimes that even spills over to the internet too, and you'll see stones like Andesine Laboradorite, or Sphene, or Sphallerite or whatever else being sold at high dollar prices for a while, til the next network fad comes along!


Pandora: Do you consider your CC garnet pictured above to have a shift or full on color change? I guess it can be subjective, but I'd call that a change and not a shift. But I've seen countless stones being sold that barely even had a shift being sold as color change, mostly on Ebay...
 
Red Spinel,

Sorry I misunderstood what you meant about fads. That's because I don't have a TV and watch those shows :lol: Thank god, or else I wouldn't have any free time at all! ;)

I hope you find a cc garnet you like!
 
I would consider mine to be a change (especially as the change IRL is more dramatic than those in the photographs).

The ones in the etsy photograph I would consider to be a shift.
 
Sounds like I am in a similar situation as RS...

I found a really neat Blue CC garnet, and the vendor photos showed a blue to red...it was a little stone, .78cts, for a reasonable price. I bought it, it is really nice!! I'd call it a slightly greenish-blue changing to a slightly purplish-red...nice sparkle. I liked it so much that I sent it to Dan Stair for a pavillion recut, which removed the window. It still faces up the same size, but it lost a little weight and is now .58cts (but it looks the same size and is SO much better cut now!!) Well worth double the price I paid for the stone/recut..so..what did I do???

I went back to the same vendor. I didn't see any other blue-red garnets for sale, but I sent them a message. Sure enough, they came up with one. They sent me pics that showed the same blue to pink/red...awesome. This time, the stone is larger, at 1.81cts (cant remember dimensions). They told me it is the same material, and going by the vendor pics it appeared to be. You can see where this is going...oh, the price? Double what the smaller stone cost, which I thought was a STEAL since it is SO much larger. But, you get what you pay for right???

I opened the box and thought "Oh, nice Amethyst, but I don't remember ordering an Amethyst?" It took me about ten minutes to put the pieces together..This was the color change garnet?? But this stone is PURPLE!!! This was at night under normal Incandescant/Halogen. Then, I moved it under flourescent and then I see a yucky color...its a greenish/bluish BROWN. That is not what I wanted/expected etc. I contacted the vendor saying how dissapointed I am...the hassle involved of sending it back to Thailand...the waiting for it..the hope that it doesn't get "lost". I mean...ugh. He claims the material is very hard to find, that he sold me the stone cheap for what it is (despite what it is not) etc. I mean, It is a very nice purple stone in the incandescent lighting..but a dark bluish/greenish Brown is not what I signed up for. He is supposed to get back to me.

So there are many times of CC garnets and they all have their different values...but I never expected to see a nice amethyst looking stone turning into almost the worst colored dravite Tourmaline ever....
 
Thats similar to what happened to me the 2 times I bought CC garnets, but the difference was that BOTH colors were ugly! At least the stone you bought is pretty on one end of the color change spectrum, mine werent, so I sent them back. But I do like my raspberry pink/copper brown garnet though, and its larger at over 2.5cts.
 
Just to clarify something ...............

Colour Shift - this is when the colour shifts from one colour on the colour wheel to the next or two colours to the side i.e. blue to purple.

Colour Change - this is when the colour jumps straight across the colour wheel i.e. red to green.

Generally colour changers are usually more expensive because changers are rarer than shifters.
 
LD|1336149505|3187551 said:
Just to clarify something ...............

Colour Shift - this is when the colour shifts from one colour on the colour wheel to the next or two colours to the side i.e. blue to purple.

Colour Change - this is when the colour jumps straight across the colour wheel i.e. red to green.

Generally colour changers are usually more expensive because changers are rarer than shifters.


Ok, I've got a rectangular, scissors cut Tourmaline of over 9cts, and its blue-green. If you turn it one way its looks blue, and the other way it looks greenish. Different light seems to affect that shift too.

Now I know thats pleochroism, but is it also considered a "color shift?"
 
RedSpinel|1336150093|3187564 said:
LD|1336149505|3187551 said:
Just to clarify something ...............

Colour Shift - this is when the colour shifts from one colour on the colour wheel to the next or two colours to the side i.e. blue to purple.

Colour Change - this is when the colour jumps straight across the colour wheel i.e. red to green.

Generally colour changers are usually more expensive because changers are rarer than shifters.


Ok, I've got a rectangular, scissors cut Tourmaline of over 9cts, and its blue-green. If you turn it one way its looks blue, and the other way it looks greenish. Different light seems to affect that shift too.

Now I know thats pleochroism, but is it also considered a "color shift?"


No. It's pleochroism.

A colour shift/colour change happens with changes in light not when the gem rotates. With shifters/changers, the whole gem appears another colour and is stable in that lighting condition. Most gems shift in colour slightly depending on lighting which is why sometimes we like our stones in daylight but not incandescent or vice versa.
 
LD|1336149505|3187551 said:
Just to clarify something ...............

Colour Shift - this is when the colour shifts from one colour on the colour wheel to the next or two colours to the side i.e. blue to purple.

Colour Change - this is when the colour jumps straight across the colour wheel i.e. red to green.

Generally colour changers are usually more expensive because changers are rarer than shifters.

I always had it that a colour shift had the colours adjacent, but colour change had them separated - ie a purple to pink-purple is shift and blue-purple to pink is a change. It doesn't have to be a jump across the wheel, just not adjacent.
 
Pandora|1336151508|3187593 said:
LD|1336149505|3187551 said:
Just to clarify something ...............

Colour Shift - this is when the colour shifts from one colour on the colour wheel to the next or two colours to the side i.e. blue to purple.

Colour Change - this is when the colour jumps straight across the colour wheel i.e. red to green.

Generally colour changers are usually more expensive because changers are rarer than shifters.

I always had it that a colour shift had the colours adjacent, but colour change had them separated - ie a purple to pink-purple is shift and blue-purple to pink is a change. It doesn't have to be a jump across the wheel, just not adjacent.


It's not often I disagree with you Pandora but I'm afraid that this is one of those times! I'm absolutely positive about the difference. The only time it's a colour changer is when it goes across the wheel which is why red/green it so prized as opposed to blue/purple (bad example but you know what I mean). As you know, my collection consists of mainly colour shift/change gemstones and it's one of those areas that I've been interested in. However, that doesn't mean I'm right!

ETA: I'm sure that I have an article somewhere from either Richard Hughes or Richard Wise outlining the differences. Will see if I can find it but it may be buried in my archives somewhere.

EEETTTTAAAA:!

Just found this written by Richard Hughes when looking for the article I mentioned above. For RedSpinel, this explains far more succinctly why pleochroism isn't the same as colour change: "Although alexandrite is strongly trichroic, its color change has nothing to do with pleochroism. Instead, like all other color-change gems, it results in a near-equal transmission of the blue-green and red portions of the spectrum, coupled with strong absorption in the yellow. Thus its color is dependant on the spectral strength of the light source. Incandescent light is strongly tilted to the red end, thus causing alexandrite to appear reddish. Daylight, is more equally balanced. Since our eyes are most sensitive to green light, the balance is tipped to the green side. The strength of the color change is related to the difference in the areas of transmission, relative to the absorption in the yellow. The greater the difference, the stronger the color change."
 
Not doing another ETA!

Vincent Pardieu described his definition: "Color shift is when a gemstone present different colors using different light as blue and purple, Color change is the same but the 2 colors are not adjacent on the color wheel (like green and purple). Some people even use the term "true color change" when the color on a different light is the complementary color on the color wheel (like green and red)... "
 
Ok..here is how I always interpreted what is color-change and what is color-shift

A color-change is when you go from either a primary color to another primary color...example Blue-Red...or, you go from a Primary color, to a secondary color that has none of the primary color in its makeup....example Red-Green.

A color-shift would be when you go from a Primary Color to a secondary color, which has that primary color in its makeup...example Blue-Purple (purple is a combination of Blue and Red...another example would be Red-Purple.

Interesting about other stones such as Tourmaline. Aside from Pleocrism (sp?) lets use the example of rubellite. Lets not turn this isn't what Rubellite is or is not...so go with it.

The first picture is how this Rubellite looks most of the time..and its the typical purplish-red/pink. But sometimes, under some lighting, it will "shift" and appear Orangish-Red/Pink.

So whats the definition of what is occuring there? is it color shifting? Or is there another term?

rubellite1.jpg

rubellite2.jpg
 
I agree with LD's definition of colour change versus colour shift. When the change is dramatic and goes to another colour on the other side of the colour wheel, it is a colour change. So green to red and blue to red are colour changers. If the two colours are next to each other on the colour wheel, they are colour shifters. Meaning blue to purple and yellow to green are colour shifters.

Then there is also the slight shifting of stone colour under different lighting. I don't think there is a set name for it though. In this case, the shift is even less dramatic than a true colour shift stone. Usually it is like red to pink or blue to violet, sort of like a half step away to the next wheel colour.
 
Chrono|1336162975|3187718 said:
I agree with LD's definition of colour change versus colour shift. When the change is dramatic and goes to another colour on the other side of the colour wheel, it is a colour change. So green to red and blue to red are colour changers. If the two colours are next to each other on the colour wheel, they are colour shifters. Meaning blue to purple and yellow to green are colour shifters.

Then there is also the slight shifting of stone colour under different lighting. I don't think there is a set name for it though. In this case, the shift is even less dramatic than a true colour shift stone. Usually it is like red to pink or blue to violet, sort of like a half step away to the next wheel colour.


I have to disagree with that. Color change is defined by a noticeable and dramatic change in color under different lighting. Dramatic doesn't need to mean red to green. It just means a change in color that is a change to a different color within a certain range. Look at a color wheel. You have your primary colors of blue, yellow and red. You then have secondary colors at violet, green and orange. Then you have your tertiary colors: yellow orange, red orange, blue violet, red violet, blue green and yellow green. Then there's everything else in between. A color change happens among primary and secondary colors. It's the tertiary colors that are a murky subject- I consider changes among tertiary colors a shift, since both potential colors contain the same primary or secondary color as they dominant hue. Going from one color to the one right next to it is a shift. Blue to blue-violet is a color shift. Going from a primary to a tertiary, color shift. Secondary to tertiary, color shift. Red orange to yellow orange is a color shift. It's when you go secondary to primary, secondary to secondary or primary to primary you have a color change. Blue to purple is a color change. Does that make any sense the way I explain it...? lol

The slight shifting under different light that you mention is just a color shift and falls into the main color shift category.
 
GET 3 FREE HCA RESULTS JOIN THE FORUM. ASK FOR HELP

Featured Topics

Top