Hi Charles,
The strength of the ferric Chloride solution is quite important, it needs to be a reasonably concentrated solution, (too slow and it doesn't give such good results, because the reaction slows after a few minutes, presumably because the surface becomes less 'clean' and doesn't react as quickly, so you need to etch it within a minute or so.). Personally, I have directly compared Nitric Acid etching to Ferric Chloride etching, and found Ferric to be noticeably superior (This is consistent with (I think) 'O' Richard Norton's article in Meteorite magazine some years back, he also discussed tint etching, which uses various chemicals to bring out features by coloring them. No too falls are the same however and I have not tried it on anything other that Gibeon, Campo, Sikhote, Brahin (and a couple of others). I expect the differing Nickel contents will produce varying results with both methods, experimentation is the best policy! ... Best Mark _____ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Charles Viau Sent: 25 November 2006 04:51 To: mark ford; meteorite-list@meteoritecentral.com Subject: Re: [meteorite-list] ACID FOR ETCHING: QUESTION While Ferric Chloride is safer, it is much slower... and it seems (to me anyway) that the etched definition is much lower.... I have found a good source for small quantities of nitric acid to be jewelers, especially those that plate gold. They mix hydrochloric with nitric to make aqua regia, an acid powerful enough to dissolve gold. Very dangerous stuff and certainly not an acid that you would ever use on a meteorite, unless you want to see it disappear... however many will sell you a small amount of nitric if you ask. Again, they use the pure stuff so be real careful... take it home wrapped in lots of paper in a box. Dilute it! Typical is a 5% Nitric solution using 100% denatured ethyl alcohol (not the isopropyl type in water) or 1 part pure nitric in 19 parts alcohol. Standard chem. 101 safety statement : Add acid into alcohol!, not alcohol into acid! , wear goggles, use latex gloves and do it in the garage, not the house... CharlyV _____ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of mark ford Sent: Thursday, November 16, 2006 10:25 AM To: meteorite-list@meteoritecentral.com Subject: Re: [meteorite-list] ACID FOR ETCHING: QUESTION Try Ferric Chloride much better and safer. - Available from electronics stores _____ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: 16 November 2006 01:45 To: meteorite-list@meteoritecentral.com Subject: [meteorite-list] ACID FOR ETCHING: QUESTION Hi to all list members! It has been a long time since I have needed a new bottle of nitric acid. So long that the last time I bought a bottle, it was at a drug store. Really! Short of going 25 miles to a collage chem store, where would be the best place to get a bottle of acid? No one around my town has any! Any help would be appreciated. Thanks, Jim Balister -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.430 / Virus Database: 268.14.7/538 - Release Date: 11/18/2006 4:48 PM -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.430 / Virus Database: 268.14.14/548 - Release Date: 11/23/2006 3:22 PM
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