>{ 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
>
>
Most of the straw-colored glass that I have seen was window glass, making
the use of arsenic in this glass only as dangerous to public health as lead
in paint.

The onset of WWI probably encouraged the shift to machine production of
glass, due to the lack of manpower.

Erica Sanborn

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