snip:
>Try this: take three panes of glass (or plexi), cut holes into one of them
>according to coin sizes and shapes, and make a sandwich. Thus
>visitors can view avers and revers from as near as they wish to

I saw something like this before, with a large magnifying lens that could
move in all four directions (on the surface in front of the exhibit) via a
sophisticated frame with tracks.   The mechanism of the lens was really
awkward and bulky, and it's use was limited to one person at a time.  I
thought it would have been easier to have several small lenses (good ones,
but inexpensive to replace) on cords.  I think the exhibit I saw was at the
Lowie Museum in Danville, CA.

Bill

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William H. Stirrat  (Bill)
Evaluator/Market Researcher              ? !
Our Minnesota Science Hall                  o
Science Museum of Minnesota          /( )\
30 East 10th Street                                    /\
St. Paul, MN  55101
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As always, opinions expressed are my own.
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