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 Post subject: Umbalite garnet... questions!
PostPosted: Fri May 13, 2016 4:04 am 
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Dear friends,
I would like to receive some info about Umbalite garnet...
It looks very similar to a good quality Rhodolite at first look, but I read that it has a different chemical composition.
As a matter of fact, it is reported that umbalite is a mixture of pyrope and spess
http://www.gemdat.org/gem-27164.html
It is mined in one single location: the Umba river.
Thus, might it be considered a rarer and more expensive kind of garnet than rhodolite?
I found that its price is around 100/150 dollar/carat on the web.
But on Gemval and on my edition of The GemGuide (2013), the price per carat of Umbalite is not reported.
Does anybody have an idea about the value?
Thanks!!!!


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 Post subject: Re: Umbalite garnet... questions!
PostPosted: Fri May 13, 2016 12:54 pm 
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Gemval is not a reliable pricing source.

There is no blue book on gem pricing. One has to define the market in which something is valued.
(Actually even the Blue Book for cars defines the market in which they value the vehicle.)

That being said, I would suggest starting with this article from the GIA,
Vanadium- and Chromium-Bearing Pink Pyrope Garnet: Characterization and Quantitative Colorimetric Analysis


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 Post subject: Re: Umbalite garnet... questions!
PostPosted: Fri May 13, 2016 1:32 pm 
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@Barbra
Thank You for the valuable suggestions!!!


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 Post subject: Re: Umbalite garnet... questions!
PostPosted: Sat May 14, 2016 4:45 am 
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Barbra Voltaire wrote:
Gemval is not a reliable pricing source.

Barbara, would you care to elaborate? I am not challenging your opinion, on the contrary I respect your industry knowledge, but it would be helpful to know why you find it unreliable. My understanding is that it is based on surveyed internet retail prices, excluding extremes, so what is wrong with it? Is there a systematic bias in Gemval's pricing that one could compensate for?


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 Post subject: Re: Umbalite garnet... questions!
PostPosted: Sat May 14, 2016 12:24 pm 
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let's take apatite for example:
http://www.gemval.com/chart.php?type=21

eBay
Image

Gem Select

A higher end offering:
AJS Gems

A lower end offering
Gem Rock Auctions

So, where are we finding the prices reflected in GemValue?
They define the market as "Apatite: average retail prices, May 2016".
All the stones above are available in a retail online market.
So where is this "retail market" used for GemValue?


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 Post subject: Re: Umbalite garnet... questions!
PostPosted: Sat May 14, 2016 1:50 pm 
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Barbra Voltaire wrote:
So where is this "retail market" used for GemValue?

They seem to be listed here. http://www.gemval.com/resources.php
Are these all expensive, high-end outlets that don't really represent the global market? I take the point that the market is different in different geographies, so perhaps Gemval represents only the top-end US market. But Gemval looks conveniently user-friendly for a rough-and-ready price guide, so it would be nice to know if there is a consistent factor by which one could adjust Gemval values to be more realistic. Or are they just all over the place?


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 Post subject: Re: Umbalite garnet... questions!
PostPosted: Sat May 14, 2016 2:20 pm 
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If I am looking to value a gem, the first thing I would do (after determining the quality of the gem from a professional standpoint: color, clarity, cut quality, treatment,) is to define exactly how and where the stone is to be replaced.
- the store where the client purchased it?
-online through, let's say through AJS
-Home Shopping Network?

Secondly, simply do some research in the defined market and list those sources on my documentation,

Even if someone brings something in that was a gift or an inheritance, the first thing I discuss is defining a market for replacement.

Yes, it involves a couple extra steps, but that's what folks pay me to do. :D

There is really no Blue Book on Gem Pricing......shortcuts perhaps. Think about it for a second. If you were doing broad research on any other topic and your sample size was 13, would you consider the findings reliable?

There is a caveat. If indeed, you are defining the replacement market to be precisely those 13 options, fair enough. But, I would still actually contact those sources personally and individually, describe what I need a value on through my eyes and get actual quotes.


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 Post subject: Re: Umbalite garnet... questions!
PostPosted: Wed Jan 30, 2019 10:49 am 
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Barbra Voltaire wrote:
If I am looking to value a gem, the first thing I would do (after determining the quality of the gem from a professional standpoint: color, clarity, cut quality, treatment,) is to define exactly how and where the stone is to be replaced.
- the store where the client purchased it?
-online through, let's say through AJS
-Home Shopping Network?

Secondly, simply do some research in the defined market and list those sources on my documentation,

Even if someone brings something in that was a gift or an inheritance, the first thing I discuss is defining a market for replacement.

Yes, it involves a couple extra steps, but that's what folks pay me to do. :D

There is really no Blue Book on Gem Pricing......shortcuts perhaps. Think about it for a second. If you were doing broad research on any other topic and your sample size was 13, would you consider the findings reliable?

There is a caveat. If indeed, you are defining the replacement market to be precisely those 13 options, fair enough. But, I would still actually contact those sources personally and individually, describe what I need a value on through my eyes and get actual quotes.


I was doing some reading on pink garnets, when I came across these couple post from Barbra, which I thought were fantastic!! So, that means I had to at least stop for second to say ....great post!!!!!

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MrAmethystguy ~ Some jokes just fluorite over my head!


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