Richard J Kinch wrote:
Christopher Tidy writes:

According to some articles I've found online, certain metallurgical
microscopes use a plain glass sheet which works by total internal
reflection rather than a semi-silvered mirror. If that's the case with
my microscope, it would make the glass much easier to find. I might even
be able to use a circular glass cover slip.

Or even try cutting some 0.015 Mylar sheet (overhead transparencies) with
scissors. Not really optically flat, but maybe worth experimenting with.

Might not be what your looking for but take a look at some of the
replacement side mirror items at your local parts store. The Help mirror
I just bought is a strange item. You can hold it to a light source and
see through it, Put it against a backer material and it becomes a good
mirror. It was a simple rectangular mirror for replacing the older style
GM truck mirrors.
Thickness wise it is maybe an 1/8"

--
Steve W.
Near Cooperstown, New York