AW: [meteorite-list] RE: POLL: rustiest most unstable known

From: Martin Altmann <altmann_at_meteoritecentral.com>
Date: Wed May 31 11:18:09 2006
Message-ID: <007101c684b7$3970c050$4f41fea9_at_name86d88d87e2>

My half cent:

>From the collector's view it is certainly of interest how high the effort
will be to stabilize his specimen, as I doubt, that the average collector
has a little lab at home, has the cash to purchase certain quantities of
irons to execute test series, to find out which method will work best for a
specific locality, nor the time to observe the treated specimens for several
years, nor is it dulcet for him to ply chemicals, whereof he is not so sure,
what they are doing exactly,
so that every conservation method to carry out exceeding oiling or a simple
varnish and a storage with desiccants is principally unacceptable.

Also a collector has to deliberate about the costs of a professional
stabilization of his specimen, as e.g. it makes not so much sense to restore
and to elaborately treat a little Campo slab, for which he paid 15 bucks. Of
course some offerors let oneself be talked round to do it for free
(even if the piece was bought elsewhere and is a locality they always warned
to take), but covertly they often will be enervated (as most of them already
work for God's pay in their profession, hehe).
Other way round it would make no sense for a dealer to spend time and money
to stabilize a Campo, Dronino or Nantan, because it wouldn't be rewarded by
the buyers, cause they are used to pay on ebay always the same price per
gram for the same mass locality and quality doesn't matter.

The chlorine problem is in such a way, that, if one buys a specimen of a
certain locality - even if it was prepared de lege artis - one NEVER can
predict whether it will rust or not and when it will start to rust,
because one simply doesn't know, how much moisture and chlorine the very
individual piece absorbed from the ground.
Of course there are localities, let's take Campo, Nantan, Dronino where from
experience the probability that one will catch a ruster is very high, and
also the opposite - Gibeon, Imilac, Mundrabilla - often are very stable,
but there are exceptions and it's simply a lottery if you will draw the
jackpot or a blank.

Of course as offeror one has a possibility to check the tendency, in simply
taking a specimen to quarantine. If an untreated cut surface kept airtight
with dessicants will after a while start fiercely to rust, one knows, that
one won't have great fun with slabs cut from this rough specimen.
(and some will think, huh, let's throw it away as fast as possible into
ebay)

But even if it will stay stable one never can't be sure. There are slices,
which stay good boys for many years and then they start to oxidise in a
sudden explosion.

Any collector should be aware, that each iron can rust and most will do rust
by.and-by. If he is not willing to take the efforts to care for the nursing
of his irons or if he has special unfavourable conditions, e.g. living in a
humid climate with sudden variations of temperature, he should not collect
iron meteorites, but stone meteorites, as they cause in general not so much
troubles (yabba yabba don't start with brown Hammami or Zag, there are only
a few exceptions).

Btw. In my eyes very harmful in regard to gain more new meteorite collectors
are those fellows, who are drilling holes in little Campos ect. and sell
them as pendants. The buyers will wear them around, will touch them, and
with the contact of sweat, soon they will have hanging a lump of crumbling
rust around the neck. You may imagine, that they never will want to have a
meteorite again.
No less or even more worse, because they should know it better, are those
sellers with their "New" stable Campos. They buy that stuff, no matter if
they knew in which soil they were found (which also doesn't say nothing,
take Morasko e.g. which were found close to each others, some are rusters,
some are as stable as wood), they maybe live in a dry desert state and they
sell it with in a few weeks. Are they sitting inside of those chunks? Do
they have trained their dogs&cats to smell the chlorine? Are they
visionaries?
I'm collecting for 25 years now, and sincerely I don't dare to judge the
stability of an entire piece from taking a simple glimpse from outside.
Or remember that seller with his gimmick of his new secret Brahin
stabilizing method. You can keep it in saltwater ect. absolutely stable for
years, he was writing, when he just had used this method for a few weeks
only. (meanwhile some of my collectors, who took some slices, reported me,
that they do rust).
Those are highly unreliable sellers.
You may wonder, why I am so affective in this respect, but I am really sick
and tired of the weekly cry for help of my collectors, who bought that stuff
under those wrong promises, I can't stand it any longer: Waaaaah my Campo is
rusting, bleeeeeeh the olivines are popping out, what shall I do...

Those sellers do not care about, they might jovially think, that it's the
buyer's fault, if he's so stupid to believe the rubbish they are telling.
But honestly, if you took such a "New" stable Campo or such a wonder-Brahin
and the stuff is rusting, cook their gooses and insist in full refund (and
don't email me, pleeeeeeeease)
If they refuse, but do have an IMCA-label, contact IMCA,
because they spoiled that fine hobby for so many newbies.

Some addition: Also care in storing irons for a constant temperature,
sudden jumps to high temperatures can have devasting effects.

Hehe, Lithium grease, applied on the tongue it may relieve your depressions
in watching your irons rusting to pulp.
NOOOOOOO just a joke! Kids, DON'T do it at home!

Buckleboo!
Martin
    
 



-----Urspr?ngliche Nachricht-----
Von: meteorite-list-bounces_at_meteoritecentral.com
[mailto:meteorite-list-bounces_at_meteoritecentral.com] Im Auftrag von R. N.
Hartman
Gesendet: Mittwoch, 31. Mai 2006 03:29
An: mark ford; meteorite-list_at_meteoritecentral.com
Betreff: Re: [meteorite-list] RE: POLL: rustiest most unstable known

Our experience:

You will not remove all the moisture that gets deep into fissures and at the
boundaries of the inclusions in an iron meteorite simply by any method if
the meteorite is treated at room temperatures. We heat the iron meteorite
in an oven to a high temperature in a protecting oil which expands the
cracks and allows a protecting oil to replace the moisture. The protecting
oil prevents discoloration and damage to the iron which would occur if
heated otherwise. It works perfectly. None of my iron meteorites rust.
The protecting oil is then swabbed over the surface and allowed to evaporate
for a few days, then the remainder is removed and the surface allowed to
fully dry, protecting the meteorite from absorbing additional external
moisture. Such an oil is ordinary ATF as used in modern automobile
transmissions. (And it is cheap!) The method was developed by my son, Jim,
and has been partially described in one of my previous articles in METEORITE
TIMES (November 2002) in which we described proper preparation of the
surface of an iron. The details using the AFT was not discussed there as it
is a bit tricky and I am not suggesting that anyone try this as I don't want
anyone to burn down their kitchens or blow their heads off, but with careful
experimentation someone experienced in lab techniques can achieve much
success. Heating carefully as described in the article should give good
results.

Other techniques have been described by various preparers and some of them
seem to be successful as well. But each iron is unique and no method works
exactly the same for any two.

Ron Hartman
Received on Wed 31 May 2006 09:36:23 AM PDT