In article <[log in to unmask]>, [log in to unmask] (Robert W.
Bradspies) wrote:

>     I am trying to locate information on an early method of getting a
> three dimensional look to an artwork by adding clear pieces of material
> to the back side of a piece of glass then covering the back with a
> reflective material such as gold or silver leaf.
>
>     This method caused the reflective material to be at different
> depths away from the viewer and gave the impression of depth in the
> art work.
>
>     If anyone has any information on such art works, or can point me in
> the direction of a possible source, I would appreciate it.
>
> Robert W. Bradspies - [log in to unmask] -- (310) 475-0624

I think that the three dimensional effect that you are talking about is
actually bas relief created by sandblasting and acid polishing or acid
etching and polishing. The process involves masking the glass and blasting or
etching away layers of material to sculpt a design or image. After the
design is etched, it is polished with a weak solution of hydrofluoric acid
which restores the translucency of the glass. The surface is then
silvered, just like a mirror, and coated with a protective film like a
varnish to prevent oxidation. The image is viewed through the glass and
appears three dimensional because it is.

The equipment to do this type of artwork is available in a number of
university art glass departments in the US. A note of caution though:
Hydrofluoric acid is one of the deadliest acids known and is very
difficult to work with. The mirror silvering process is also very tricky
and the techniques involved in carving glass take years to develop.

Richard E. Duggan                   |
Chairman, Exhibits Department       |   808-848-4178 (vox)
Bishop Museum                       |
1525 Bernice Street                 |   808-848-7897 (fax)
PO Box 19000                        |
Honolulu, HI 96817                  |   [log in to unmask]
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