[meteorite-list] Rusty rocks
Since the list has a large combined knowledge and plenty of previous experience what is the best way to dry out meteorites gathered from a wet environment? would soaking in anhydrous alcohol or ether prior to oven drying do a better job of removing moisture from the interior? Some of the meteorites I have found locally are sweating rust even after repeated drying . Since meteorites conduct electricity has anyone ever tried using it to stabilize rusty rocks? seems to me the electricity would get right to the metal remove the water and reduce the oxidation but I am not sure if it would cause other undesirable effects. On another note after playing fetch using nwa 869 meteorites for several months, my Lab Trixie has found her first meteorite, a small ordinary chondrite. Best regards Steve - Sponsored Link Rates near 39yr lows. $420,000 Loan for $1399/mo - Calculate new house payment__ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Rusty rocks-- Lawrencite Disease, Trixie
There is a name for this Rusty Rock condition which veterans of collecting know as Lawrencite disease. Lawrencite is the mineral Iron/Nickel Chloride (Fe,Ni)Cl2. In fact Lawrencite's type classification location was a Georgia USA Meteorite. Drying out a meteorite isn't an complete answer because Lawrencite is a moisture attractant(deliquescencent) that facilitates --in catalyst fashion, the rebinding of free iron with water derived oxygen, creating rust and Hydrochloric acid. The chlorine is never used up but recycled so long as there is iron and water. Elton PS: Don't know about the electrical current issue other than sounds like a plating problem PPS: Congrats to the meteorite sniffing dog, Trixie do tell us more!. Don't worry; she can't catch Lawrencite disease. From Bill Cordua's Site:http://www.uwrf.edu/~wc01/SickMeteors.html Sick Meteorites Meteorites have broken off asteroids, whirled through space for billions of years, survived a fiery passage through the earth's atmosphere and bashed into the planet's surface. After this turbulent history, one would not expect these meteorites would meet one of their greatest danger residing in a cabinet in a museum. Yet it is here that they catch the dreaded lawrencite disease. Once caught, the meteorite turns rusty, exudes green or brown goo and eventually falls to pieces. Only an air-tight sealing in dry nitrogen gas seems to hold off final destruction. These meteorites need to be on life support! Of course lawrencite disease is not a biological condition like human diseases and it is definitely not catching! It is a kind of chemical weathering that afflicts meteorites that contain the mineral lawrencite. Lawrencite is iron chloride (FeCl2). It is a soft green to brown hexagonal mineral that forms small masses or coatings along the boundaries between the iron-nickel alloy minerals (such as taenite and kamacite) that make up the bulk of iron meteorites. The taenite and kamacite are what show up as the brightly shining tabular crystals seen on polished iron meteorite surfaces. The lawrencite films along the grain boundaries don't often show up on these polished surfaces, at least not at first. They will soon make their presence known as the meteorite is exposed to air and water. Lawrencite shows a property called deliquescence. This means it absorbs water from the air and liquefies. The liquefaction produces the brown to green gooey sludge which begins to form around the shiny metallic alloys. This sludge consists of iron oxides plus hydrochloric acid, which attacks the other iron minerals, making more sludge and so forth. Eventually the affected areas spread, wedge apart and alter the other minerals and eventually reduce the meteorite sample to a pile of rusty debris. There is no cure - short of sealing the meteorite away. A meteorite type called pallasite is particularly vulnerable to this conditions. These meteorites contain deep green clear olivine crystals set in a matrix of nickel;-iron alloys. Slabbed and polished samples of pallasites are beautiful and expensive. However, if the lawrencite disease strikes, the sample deteriorates rapidly, with the olivine crystals falling out as the alloys rust away. Always look for incipient rusty or gooey areas along grain boundaries before buying one of these! So it goes with meteorites foolish enough to leave the safety of pure space for the impure chemical soup we lovingly call our earth's environment. - Dr. Bill Cordua, U. Wisconsin - River Falls References: Norton, O. Richard, 1994, Rocks from Space, Mountain Publishing Co,, . Palache, C., H. Berman and C. Frondell, 1951, Dana's System of Mineralogy, 7th. edition, vol. I and II, John Wiley Publishers, New York. --- Steve Dunklee [EMAIL PROTECTED] wrote: On another note after playing fetch using nwa 869 meteorites for several months, my Lab Trixie has found her first meteorite, a small ordinary chondrite. Best regards Steve __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Rusty rocks-- Lawrencite Disease, Correction
OOps.. Type class locale for Lawrencite was the Tazewell meteorite, Claiborne Co., Tennessee, USA not a Georgia meteorite but it has been found in Georgia meteorites. So much for facts from memory. Any treatment has to remove the chlorine ions/compounds. I suggest I could place a freshly fallen iron in distileld degassed water, seal it and it would form a thin rind of Iron Oxide but remain pristine for decades. Elton --- Mr EMan [EMAIL PROTECTED] wrote: In fact Lawrencite's type classification location was a Georgia USA Meteorite. __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Rusty rocks
way to go Trixie. i'll have to see if i can train my dogs. Happy Thanksgiving everyone. take care susan - Original Message - From: Steve Dunklee To: meteorite-list@meteoritecentral.com Sent: Wednesday, November 22, 2006 11:05 AM Subject: [meteorite-list] Rusty rocks Since the list has a large combined knowledge and plenty of previous experience what is the best way to dry out meteorites gathered from a wet environment? would soaking in anhydrous alcohol or ether prior to oven drying do a better job of removing moisture from the interior? Some of the meteorites I have found locally are sweating rust even after repeated drying . Since meteorites conduct electricity has anyone ever tried using it to stabilize rusty rocks? seems to me the electricity would get right to the metal remove the water and reduce the oxidation but I am not sure if it would cause other undesirable effects. On another note after playing fetch using nwa 869 meteorites for several months, my Lab Trixie has found her first meteorite, a small ordinary chondrite. Best regards Steve -- Sponsored Link Rates near 39yr lows. $420,000 Loan for $1399/mo - Calculate new house payment -- __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Rusty rocks
Hi List members, Steve and Trixie! I am sure Trixie is going to get an extra piece of turkey. I would like to know also how did she find the meteorite and where. Did you take her to the desert and let her loose and she sniffed until she found one or how? This could make a nice Thanksgiving story to read after we all stuff ourselves with the turkey dinner. Happy Thanksgiving and best regards, Moni From: Steve Dunklee [EMAIL PROTECTED] To: meteorite-list@meteoritecentral.com Subject: [meteorite-list] Rusty rocks Date: Wed, 22 Nov 2006 09:05:40 -0800 (PST) Since the list has a large combined knowledge and plenty of previous experience what is the best way to dry out meteorites gathered from a wet environment? would soaking in anhydrous alcohol or ether prior to oven drying do a better job of removing moisture from the interior? Some of the meteorites I have found locally are sweating rust even after repeated drying . Since meteorites conduct electricity has anyone ever tried using it to stabilize rusty rocks? seems to me the electricity would get right to the metal remove the water and reduce the oxidation but I am not sure if it would cause other undesirable effects. On another note after playing fetch using nwa 869 meteorites for several months, my Lab Trixie has found her first meteorite, a small ordinary chondrite. Best regards Steve _ Fixing up the home? Live Search can help http://imagine-windowslive.com/search/kits/default.aspx?kit=improvelocale=en-USsource=hmemailtaglinenov06FORM=WLMTAG __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
