{ SEQ CHAPTER \h \r 1}I hope to do a follow-up article on selenium and arsenic as decolorants.  The
earliest reference I have found for selenium as a decolorant in the US is 1895.
Selenium is still used as a decolorant in the US.  It is not the culprit for the
solarized amber glass (often called “straw-colored glass” in collectors’
literature).  I have two chemistry articles that show through experiments that
more than one chemical combination can create the effect, but key ingredient
is arsenic – not selenium.  When I spoke to a chemist at a bottle manufacturer
about nine years ago, he was completely surprised at the idea that selenium
would affect glass color.

As to time, the collectors are probably correct, although on report stated that a
bottle from (if my memory is correct) about the 1950s was solarized amber.  I
can’t completely support this yet, but the use of selenium and arsenic in
combination was used by some companies, apparently in response to the
wartime pressure and the change from mouth-blown to machine production,
beginning about 1915 or so.  By about 1930, most had caught on the color
change (or found better formulae – don’t know which yet), and the “straw-
colored-glass” era was generally over.

Bill




> Selenium was used as a clalrifying agent AFTER the supplies of
> Manganese ran out.  On top of that, not everybody used it.  On top of
> that, those that did did so for varying lengths of time.  It creates
> another kind of solorized glass - Amber.  This was discarded in the
> depression era since it was cheaper to color glass than clarify it.
>
> Time to offer a rare opinion: There is a special place in perdition
> for whoever came up with that "Lima Beans through a Baby" green color
> so popular in the depression.
>
> :-(
>
>
> Smoke (Michael A.) Pfeiffer, RPA
> Ozark-St. Francis National Forests
> 605 West Main Street
> Russellville, Arkansas 72801
> (479) 968-2354  Ext. 233
> e-mail:  [log in to unmask]
>
> It is easier to get forgiveness than permission.
>
>
>
>
>              Carl Barna
>              <[log in to unmask]
>              ov>                                   To
>              Sent by:                  [log in to unmask]
>              HISTORICAL                                   cc
>              ARCHAEOLOGY
>              <[log in to unmask]
>              Subject >                         Re: manganese clarified
>              glass date
>
>
>              09/22/2004 02:51
>              PM
>
>
>              Please respond to
>                 HISTORICAL
>                 ARCHAEOLOGY
>              <[log in to unmask]
>                      >
>
>
>
>
>
>
> I thought the purple color was caused by Selenium, the supply of which
> was cut off by WW I.
>
> Carl "Slow Digger' Barna
> Regional Historian
> BLM Colorado State Office