[meteorite-list] Mohr's value for stoney meteorites

[MexicoDoug at aol.com]

Walter N. wrote:
>>I guess the best way to find out is just go  ahead and do it.
ONE THOUGHT - Why distilled water? I always use  tap.<<
 
Hola there again, The "Just do it" jingle has a lot going for it in this  
field.  After you just do it...please just tell it!
 
I have a nice 8" saw (which is why the blade prices I quoted were a bit  high 
- sorry).  The distilled water is basically for the same reason you  want to 
put distilled water in your car's radiator, never tap.  People do  it of 
course but then the steely insides of their circulatory system begin to  corrode 
and make this ugly brown gunk (meteorite cyanide) and car gets a  case of what 
meteorite people know better informally as Lawrencite Disease,  which you can 
read about attacking iron meteorites in O. Richard Norton's  classic book 
(Illustrated by his talented wife, Dorothy), "Rocks from  Space".  
 
While the stony meteorites don't have symptoms immediately as bad as the  
irons, like concrete, they do absorbe a lot of water.  You can experiment  to 
find out how much with a cut open meteorite, a precision scale and an  oven.  
It'll take about three hours at 160 170 degrees F to start talking  turkey w/r to 
drying them.  Tap water any some other forms of chlorinated  water releases 
halide ions and as an atom is possibly involved in the catalytic  oxidation of 
iron.  A stony which is not to far weathered (i.e., has a good  quantity of  
its reduced iron flecks intact, among other measures) like a  sponge will get 
impregnated with the suspected bad stuff mentioned and  eventually your 
beautiful slice which had white steely reflections will develop  amber brown measles 
in there place.  It can be repolished as many  undoubtably are sadly on eBay, 
but it won't last shiny forever for you can  suspect why.  
 
Using tap water is a classic case of irresponsibility in meteoritics though  
undoubtably someone out there in my cyberzoological garden will defend  it.  
(May they come forth so I put them on my piddly black list of  suppliers).  
Multiple alcohol soaks is way to go for highest  drying efficiency and 
contaminant removal.  Once should be fine iuf  you use distilled H20 and maybe 
unnecessary in that case.  But if you use  anything besides pure alcohol or distilled 
water then you really should be doing  alcohol soaks.  Each saok can remove a 
heafty % of the corrosives.   While you do it, you can try to comfort yourself 
with the knowledge that  meteorites are special compared to 99.999995% of the 
rest of the Earth rocks due  to their containing reduced iron that is 
vulnerable to rusting (and chlorine  also is the trick to dumping corrosive table salt 
in the water since ther are  alway sodium ions in these cocktails looking for 
partners.)  A beautiful  geode or agate doesn't mind tap water because it is 
quite stable.  This is  a case of one rock's cosmetic bath is another rock's 
poison.
 
Hope that clears it up more than mud.  Please read up on it, I am sure  I 
missed a few good thoughts on this and interpreted a couple of things too  
conservatively, but that's how I look at the world,
 
Saludos, Doug  (best oven temp is about 160 deg F for an hour  min.  You may 
"just" be dealing with NWA's but the pride you'll probably  have in your 
product will probably be woth the inconvenience many times over,  not to mention in 
helping you develop good technique for more financially  challenging 
meteorite situations.  But some people use IR heat lamps  (available at home depot and 
using less power) with alledgedly superb  results...(PS another expert out 
there signs messages JWG.  I am not sure  if he can add to this on blades, but 
as you experiment more he is also nice  oracle to have up your sleeve and 
kindly shares  info.)