Merelani Mint Garnet Q''s???

[icekid]

Date: 6/2/2009 9:27:46 PM
Author: Chrono

Date: 6/2/2009 3:12:15 PM
Author: tourmaline_lover

Date: 6/1/2009 11:30:08 AM
Author: PrecisionGem
what qualifies a green garnet to be a Merelani Mint is that it comes from Merelani Tanzania. Merelani is a location. All these stones are green grossular garnets, as is Tsavorite. Just because it comes from Merelani, doesn''t mean it''s the color you are looking for either. These green garnets are found in Kenya and other locations in Tanzania. As they get darker, then they are sold as Tsavorite. Technically, Tsavorite denotes a location too, which would be the Tsavo area of Kenya. Most people will call any of the darker green grossular garnets Tsavorite. Many of the stones are coming from Tanzani in an area very close to the Kenyan border.

I don''t know about that Gene because there''s a heated conversation going on about that right now somewhere else. Is it called Merelani because it''s from Merelani Tanzania, or is it called Merelani because it''s a unique cololred mint green grossular garnet that you can''t find anywhere else?

I thought it''s a Meralani because it''s a unique mint green grossular that is only found in the Meralani area? I know there are some who try to pass off other yellow green or light green grossular garnets as Meralani even though that is technically incorrect.

This is my understanding, as well.

 

[T L]

Date: 6/2/2009 9:27:46 PM
Author: Chrono

Date: 6/2/2009 3:12:15 PM
Author: tourmaline_lover

Date: 6/1/2009 11:30:08 AM
Author: PrecisionGem
what qualifies a green garnet to be a Merelani Mint is that it comes from Merelani Tanzania. Merelani is a location. All these stones are green grossular garnets, as is Tsavorite. Just because it comes from Merelani, doesn''t mean it''s the color you are looking for either. These green garnets are found in Kenya and other locations in Tanzania. As they get darker, then they are sold as Tsavorite. Technically, Tsavorite denotes a location too, which would be the Tsavo area of Kenya. Most people will call any of the darker green grossular garnets Tsavorite. Many of the stones are coming from Tanzani in an area very close to the Kenyan border.

I don''t know about that Gene because there''s a heated conversation going on about that right now somewhere else. Is it called Merelani because it''s from Merelani Tanzania, or is it called Merelani because it''s a unique cololred mint green grossular garnet that you can''t find anywhere else?

I thought it''s a Meralani because it''s a unique mint green grossular that is only found in the Meralani area? I know there are some who try to pass off other yellow green or light green grossular garnets as Meralani even though that is technically incorrect.

Then I would think that the Merelani''s are unique in coloration and found no where else. That''s what happens when origins are assigned to marketing names for gems. It gets confusing for everyone, just like the whole "Paraiba" debate.

 

[chrono]

Date: 6/2/2009 10:00:09 PM
Author: tourmaline_lover

Then I would think that the Merelani''s are unique in coloration and found no where else. That''s what happens when origins are assigned to marketing names for gems. It gets confusing for everyone, just like the whole ''Paraiba'' debate.

Agreed. It gets very messy for everyone involved and the consumer is usually at the losing end.

 

[icekid]

Date: 6/2/2009 10:02:40 PM
Author: Chrono

Date: 6/2/2009 10:00:09 PM
Author: tourmaline_lover

Then I would think that the Merelani''s are unique in coloration and found no where else. That''s what happens when origins are assigned to marketing names for gems. It gets confusing for everyone, just like the whole ''Paraiba'' debate.

Agreed. It gets very messy for everyone involved and the consumer is usually at the losing end.

I really think this is true! lots of confusion, misrepresentation, etc.

 

[PrecisionGem]

There are mint green garnets found in Kenya and other parts of Tanzania, not just Merelani. Just because a stone comes from Merelani, doesn''t mean it''s great color. I have some some Kenyan stones that are fantastic mint green.

A similar thing is going on with spessartite. People toss the word "Mandarin" around as a color. Mandarin is a variety of spessartine mined in Namibia. A Nigerian stone, even though it has perfect "fanta" orange color, should not be called "Mandarin".

I''ll be in Tanzania, right next to Merelani at the end of the month. I''m sure I''ll see green garnets from other area''s also while I''m there. It will be interesting to see what the locals call them, and how they all compare.

 

[chrono]

Date: 6/2/2009 10:46:02 PM
Author: PrecisionGem
There are mint green garnets found in Kenya and other parts of Tanzania, not just Merelani. Just because a stone comes from Merelani, doesn''t mean it''s great color. I have some some Kenyan stones that are fantastic mint green.

A similar thing is going on with spessartite. People toss the word ''Mandarin'' around as a color. Mandarin is a variety of spessartine mined in Namibia. A Nigerian stone, even though it has perfect ''fanta'' orange color, should not be called ''Mandarin''.

I''ll be in Tanzania, right next to Merelani at the end of the month. I''m sure I''ll see green garnets from other area''s also while I''m there. It will be interesting to see what the locals call them, and how they all compare.

Thank you, Gene.

 

[T L]

Gene,
Not to hijack the thread, but what is the difference between a Mandarin orange spessartite from Namibia and one of the same exact color from Nigeria or Tanzania or whereever? That's not a name that's got an origin assigned to it, so I'm confused. In fact, Harriet told me that her Loliondo spessartite is a true Mandarin. If you want to start a new thread to answer this question, please do.

 

[chrono]

TL,
In this case, it sounds like Harriet is using the term Mandarin to describe a colour reminiscent to the Mandarin Namabian spessartites. As in the colour of a mandarine orange, perhaps?

 

[T L]

OMG - I'm sooooo confused. Okay, I'll just call my spess "Fanta" color, and drop the word "Mandarin" because it's only for Namibian material.

Or is "Fanta' only assigned to stones from Norway?

Speaking of Fanta, I think I could use a drink right now.

 

[sleepyspinel]

Just from the first picture... very bright and clean looking! Glad you like the color, I had a good feeling about that stone

 

[sleepyspinel]

As far as capturing the right color... make sure your camera is white balanced (might need to read the manual for that), and I would try shooting in the shade of a bright day... northern light exposure or with over head fluorescents. Those light sources tend to have more blue component in them and will bring out the slightly bluish green that you are looking for

Its a nice geometric setting and a beautifully cut stone. I am truly happy you did take the chance!

 

[sleepyspinel]

For the naming thing... point is Merelani is marketing. I think that a mint green garnet can come from multiple locales and that they should be judged on their color, cut and clarity. I have seen material from purportedly different areas and they all look similar. Obviously there are variations in precise tone and saturation but those variations are no different than those encountered by the mining run from a particular area.

Thus I think it a fair and safe bet to just call them mint green grossular garnets

 

[T L]

Date: 6/2/2009 11:27:58 PM
Author: sleepyspinel
For the naming thing... point is Merelani is marketing. I think that a mint green garnet can come from multiple locales and that they should be judged on their color, cut and clarity. I have seen material from purportedly different areas and they all look similar. Obviously there are variations in precise tone and saturation but those variations are no different than those encountered by the mining run from a particular area.

Thus I think it a fair and safe bet to just call them mint green grossular garnets

I AGREE 100%!!

 

[chrono]

Date: 6/2/2009 11:27:58 PM
Author: sleepyspinel
For the naming thing... point is Merelani is marketing. I think that a mint green garnet can come from multiple locales and that they should be judged on their color, cut and clarity. I have seen material from purportedly different areas and they all look similar. Obviously there are variations in precise tone and saturation but those variations are no different than those encountered by the mining run from a particular area.

Thus I think it a fair and safe bet to just call them mint green grossular garnets

Simple and safe enough.

 

[sleepyspinel]

now on to the Mandarin issue...

The orange spessartites from Namibia have a very high (relatively speaking) concentration of Manganese... the metal coloring agent to attain the spectral orange hue in those stones. These stones do not have much iron, which is supposed to impart a darker tone ie brownish component and/or red component of the overall color. Apparantly they were named by the site holder of the first mines upon discovery (several names were coined and eventually settled on "Mandarin").

The nigerian stones typically have more iron... to varying degrees which means some likely have very little iron at all and guess what?!? they look highly similar to the Namibian material (the low iron, high manganese). One can do the name game all day, tangerine, fanta, pumpkin, insert your favorite orange colored object or food

I''ve read that really high manganese can result in black inclusions which one can see more frequently in the Namibian material... and I have seen similar inclusions in material from Nigeria.

The most logical thing in my opinion is to call all of them orange spessartite garnets and then assign color grades to convery more accurately how truly orange... what if any yellow or red components are present... with tone and saturation.

The scientific way is certainly not romantic and does not promote fanciful ideas of far off lands, exotic as they might be but I feel that it would greatly reduce the controversy inherent in color definitions based on non-fixed references... not all mandarin oranges are a specific color... at least not in my supermarket

 

[T L]

Date: 6/2/2009 11:41:01 PM
Author: sleepyspinel
now on to the Mandarin issue...

The orange spessartites from Namibia have a very high (relatively speaking) concentration of Manganese... the metal coloring agent to attain the spectral orange hue in those stones. These stones do not have much iron, which is supposed to impart a darker tone ie brownish component and/or red component of the overall color. Apparantly they were named by the site holder of the first mines upon discovery (several names were coined and eventually settled on 'Mandarin').

The nigerian stones typically have more iron... to varying degrees which means some likely have very little iron at all and guess what?!? they look highly similar to the Namibian material (the low iron, high manganese). One can do the name game all day, tangerine, fanta, pumpkin, insert your favorite orange colored object or food

I've read that really high manganese can result in black inclusions which one can see more frequently in the Namibian material... and I have seen similar inclusions in material from Nigeria.

The most logical thing in my opinion is to call all of them orange spessartite garnets and then assign color grades to convery more accurately how truly orange... what if any yellow or red components are present... with tone and saturation.

The scientific way is certainly not romantic and does not promote fanciful ideas of far off lands, exotic as they might be but I feel that it would greatly reduce the controversy inherent in color definitions based on non-fixed references... not all mandarin oranges are a specific color... at least not in my supermarket

My spess has some black inclusions visible only with a 10x loupe. I don't know if it's from Namibia or Nigeria. I've seen those inclusions in some neon orange Loliondo rough as well.

Heaven forbid that the people marketing these stones stick to science!!

 

[PrecisionGem]

I believe that the term "Mandarian" was trademarked by the originators of the Namibia find, and only applies to stones from this location. To call a spessartite from Tanzanian a Mandarian wouldn''t be correct. It was more of a marketing thing, it sounds nice, so people tend to call a nice colored spessartite Mandarine since it sounds more expensive.

 

[T L]

Well, if they trademarked the name, I agree that you are not supposed to call your Nigerian or Tanzanian, or even your Canadian orange spessartite (yes I''ve seen orange spess from Canada), "Mandarin." But if I do call my stone "Mandarin" from time to time, I hope you promise not to tell on me.

LOL!!

 

[chrono]

My Loliondo rough shows some black Mangenese inclusions which Jeff managed to cut out. Based on that, I presume my spessartite has a high Mangenese and low iron content?

 

[sleepyspinel]

I think that a spectrophotometer would be needed to be definitive, however based on the coloration (lack of strong red/brown component) would suggest not much Iron, and while the black inclusions could be some *other* impurity... manganese is a good bet on that front. I unfortunately do not have the tools to prove that, and I am just going on reports from others in the trade. Maybe they will have a symposium on Garnets that have that sort of info for the spessies...

Date: 6/3/2009 11:54:45 AM
Author: Chrono
My Loliondo rough shows some black Mangenese inclusions which Jeff managed to cut out. Based on that, I presume my spessartite has a high Mangenese and low iron content?

 

[stepcutnut]

Interesting debate!

Kind of funny how some people get wrapped up in names and lingo!!!

Probably should have posted my Mint in it's own thread

 

[stepcutnut]

Just out of curiosity-what would make my mint fluor. orange??? I will go searching, but thought someone might already know the answer

 

[sleepyspinel]

Very observant! All three of mine do so and material I had tested on Pala stock responded the same way. Glad to hear yours does as well. No publication of this has been made to my knowledge.

 

[stepcutnut]

Date: 6/4/2009 11:45:35 AM
Author: sleepyspinel
Very observant! All three of mine do so and material I had tested on Pala stock responded the same way. Glad to hear yours does as well. No publication of this has been made to my knowledge.

SS-I did try and research it a little and came up empty handed, do you know what element/elements make it fluor orange???

 

[sleepyspinel]

I do not know, sorry. I know that the more saturated material aka Tsavorite, does not exhibit this quality. HTH.

 

[T L]

I found this quotation on the net. My mint garnet also fluoresces. I wonder if tsavorites fluoresce, but it''s a weak fluorescence.

In A Guide in Color to Precious and Semiprecious Stones, Jaroslav Bauer and Vladimir Bouska state that, “In contrast to other garnets, grossular strongly luminesces in ultraviolet light.” Since the refractive indices of grossular and synthetic spinel are similar and both frequently house rod and acicular inclusions, Dr. Liddicoat advises that grossular’s “weak green fluorescence to shortwave” and “weak orange to longwave” may be helpful in identification.

 

[Stone Hunter]

Date: 6/2/2009 4:11:26 PM
Author: stepcutnut
I would say this is the closest so far-almost right on for color, I''ll keep working

Looks like you got a keeper!! Congrats!!

 

[T L]

Bizarre!! This is my mint fluorescing a deep orange color, although for some reason it looks pinkish purple in the pic.

Is this what you (SS & SCN) see?

 

[sleepyspinel]

Mine turn a bright neon orange... very weird but nice just the same! The ccd of your digicam has a very difficult time with UV light and interprets it as purple and it usually fails to capture the true fluor unless you also have a decent amount of ambient light as well (non-UV).

 

[T L]

It fluoresces a bright neon orange as well. I wasn''t sure how to describe it. Do all green grossulars do this?