[NHCOLL-L:4499] Epoxy removal from minerals

[Bob Glotzhober]

Many years ago some exhibit designer used huge globs of epoxy to glue
brass support rods to two of our minerals for exhibit purposes. How do I
remove the epoxy and brass rods?

 

One person suggested deep freezing, followed by directed blows to the
brass or the epoxy - but I'm concerned that might shatter the mineral
samples too. (I do have a freeze-drier accessible that could drop the
temperature to -5 F ; or if I put them in the condensing chamber, -55
F.) As it might possibly make a difference in treatment, here are
descriptions of the two mineral chunks:

 

Cat. No. N5580. Flint Ridge flint. 155mm x 85mm x 80mm. Weight 1489.9
grams.  The color is orange, with white and dark orange areas and two
small areas 

of inclusion of whitish-clear quartz crystals.

 

Cat. No. N3922. Galena.  155mm x 130mm x 115mm. Weight roughly 10
pounds/2 ounces (I don't have a very accurate scale that weighs in this
range.)

The color is a dark charcoal, with a thin lower base of grey limestone
matrix that it is sitting upon.

 

Any suggestions and advise is deeply appreciated. They have sat around
the collections for many years in this condition - so I'm not in any
rush, but the brass rods do make storage awkward and I'd like to correct
the past mis-deed!

 

Bob Glotzhober

 

====================

Robert C. Glotzhober                  614/ 298-2054

Senior Curator, Natural History    bglotzhober at ohiohistory.org

Ohio Historical Society               Fax: 614/ 297-2546

1982 Velma Avenue

Columbus, Ohio 43211-2497

Visit the website of the Ohio Historical Society at:
www.ohiohistory.org <http://www.ohiohistory.org>  and check out our
online collections catalog.

Visit the Ohio Odonata website at:
http://www.marietta.edu/~odonata/index.html
<http://www.marietta.edu/~odonata/index.html> 

 

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