Linda,

I think the best method would be to use Gram's or Lugol's Iodine.
This will remove the silver deposits immediately.  It also may be
more readily available.

Another "Food for Thought",

You could use a very dilute solution of Gram's iodine to take out 
the heavy background staining of your GMS (if you cooked it too long,
and who hasn't done that?).  You can fiddle (yes I said "fiddle") around 
with the dilution/time of this de-staining technique to your descresion 
as it will eventually take all of the silver out of your stain.  
Try it, you may like it.

Donald G. Awbrey, HT(ASCP) QIHC
Image Analysis / Electron Microscopy
donaldawbrey@texashealth.org 
donaldawbrey@hotmail.com



-----Original Message-----
From: Linda Hall [mailto:lhall@gene.COM]
Sent: Friday, November 02, 2001 10:39 AM
To: Karen Pawlowski
Cc: Histology Net List Server (E-Mail)
Subject: Re: Method for Removal of Silver Deposits on Glassware


Another good way to remove silver deposits is to use Potassium Dichromate.
It's also corrosive, but perhaps a little better than Nitric Acid!

Karen Pawlowski wrote:

> Hi all,
>
> An associate of mine, Kumathu Paulose, asked if I would post the
> following method that he developed for anyone who wants it. I haven't
> tried it, but I know that he is a very experienced histotechnician.
> I hope that someone finds it useful and I'm sure he would appreciate
> feedback. Just post it to the net and I'll make sure he gets it.
>
> Karen Pawlowski
>
> Removal of Silver Deposits from Glassware and Plastic Dishes
>
> In the histology laboratory, metallic silver is often deposited on
> glassware and plastic dishes after the use of silver stains.  This
> deposit of silver can be easily removed within a few seconds by the
> following method.
>
> Pour concentrated nitric acid into the container having the silver
> deposit. The metallic silver reacts with the nitric acid to form silver
> nitrate and hydrogen is liberated according to the following equation:
>
> Ag2 + 2HNO3 -> 2AgNO3 +H2(released)
>
> All of the silver deposits from the container will be removed in less
> than one minute.  This reaction needs to be carried out under a fume
> hood wearing gloves.  Care should be taken when handling strong acid.