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Grading, was Re: Meteorites-do you sell your loved ones?



Kevin brings up some interesting points about grading.

I wish every dealer had high-grade digital photos of
all specimens that were above average in quality.

I don't mind spending more for high quality, but I feel
a bit annoyed to get a specimen that doesn't display
properties that are representative of the type - for
example, as Kevin says, a Allende specimen should
exhibit CAI's, and an impact melt should show signs
of impact and melting, by all means sell me a brecciated
specimen, but hey, where's the brecciation? Just what does
oriented with flow lines mean? Shouldn't it be round?

Sometimes I feel that dealers are the only ones that get the best stuff,
that I should become a dealer, buy a few kilos, keep the
one best specimen for myself, and sell the rest. My collection
would be free because the markup would pay for what I keep.
This kind of behavior should only be justified if I offered
some service of value in exchange - such as that pictorial
catalog I mentioned.

Many dealers do have images but some are pretty hard to see
because they've been compressed too much or taken under
poor conditions, etc.

I understand how difficult this is to do, updating catalogs
on the web is time-consuming. But, would you buy a diamond ring 
based on a text description?

Here is a grade guide that I propose as a start - I only spent
a minute on it and it's incomplete - it's dufficult to be
complete and cover all the issues - this grading scale focusses
only upon appearances, deterioration will tend to lower grades over time.

            For individuals                  For slices
            ------------------------------   -----------------------------------
Grade A+    - 100% fusion crust, oriented

Grade A     - 100% fusion crust              edge is fully crusted
              no chips                       displays all properties of its type 

Grade B     - 90% fusion crust               displays most properties of its type
                                             some rusting of metal

Grade C          ...

Grade D       fragment, no crust

Grade E       waethered, rusted fragment
                                             

MARSROX@aol.com wrote:

> We've all purchased
> specimens that weren't Grade "A" although we paid a good price. 
>
> Poor slicing, the wrong lubricant that
> led to the specimen "bleeding", and not much elbow grease going into the
> polishing.  

> Don't tell me that a specimen of
> tired Allende w/o a CAI in sight is worth the same as a piece with a
> brilliant, white CAI and primary and secondary crust. 

> Everything collectible that I can
> think of is sold by graded condition.  We need to start becoming more
> critically descriptive in our marketing.

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