I have posted a picture of a wall mirror.

http://www.box.net/shared/static/s56crqa535.jpg

The scalloped edge has me puzzled. From a distance it looks as if the
individual hollows have been ground out. But in fact they are a series
of 'flake scars', in the terminology of lithic technology.

The effect is crude, but I guess it required the skill of a Mousterian knapper. 

Does anybody know how this flaking was done without damaging the
glass?

Is there an official name for this decorative technique and is it a technique associated only with art deco style?