Good afternoon fellow MuseumLers - I also note that the specific gravity
equipment only has a weight range of up to 50 grams and actually uses either
"tap water" or "stream water" as the fluid. So David's concerns are
completely valid for historic/museum metal objects. Even the website
mentions that the metal must be "pure". How many of the metal objects will
be "pure"? Isn't that what the volunteers are trying to determine? I don't
think specific gravity will be much help for most metal objects in a
historic/museum setting.
Regards,
Margaret (Meg) Geiss-Mooney
Textile/Costume Conservator
Professional Associate, AIC
[log in to unmask]


I would just gently observe that dunking any object or artifact into
"mineral water" is not excatly non-intrusive, and since myself and my
colleagues in conservation spent a lot of energy and time in advising
people NOT to expose their objects to elevated moisture RH let alone
water, this would obviously conflict with that. So, I think that specific
gravity might first seem to be an attractive
approach but not for historic and museum objects.

On 6/28/07, Erik Heikkenen <[log in to unmask]> wrote:
>    How large of an object is it?   If it is small, (e.g. coins, jewelry,
> etc).  I would recommend a basic Specific Gravity test.  You can purchase
a
> smaller Specific Gravity Kit at most "rock shops" or online at any lab
> supply website.
>     Specific Gravity testing is non intrusive and you will not damage the
> objects, they will however, get wet, with mineral water, so take that into
> consideration.  And remember to dry the objects properly (pat dry not
rub).
>
> Here's a helpful link: http://www.mineralab.com/Specific%20Gravity.htm.

No virus found in this outgoing message.
Checked by AVG Free Edition. 
Version: 7.5.476 / Virus Database: 269.9.10/876 - Release Date: 6/28/2007
10:56 AM
 

=========================================================
Important Subscriber Information:

The Museum-L FAQ file is located at http://www.finalchapter.com/museum-l-faq/ . You may obtain detailed information about the listserv commands by sending a one line e-mail message to [log in to unmask] . The body of the message should read "help" (without the quotes).

If you decide to leave Museum-L, please send a one line e-mail message to [log in to unmask] . The body of the message should read "Signoff Museum-L" (without the quotes).