The original publication by Perrault refers clearly to the word "verre". There is a controversy in French because author Balzac, 150 years later, proposed it could be a typo and should read "vair"... But it most likely is not the case.
The engineering analysis was tremendously fun. However, the explanation for the appearance of the glass slipper, is that it was never in the original story, which was french, and in that the shoe was made of vair, or grey squirrel fur, and vair sounds like verre, which is, of course, glass (http://www.iletaitunehistoire.com/genres/contes-legendes/lire/cendrillon-biblidcon_029).
Talking about something similar, have you heard of the concept of Space elevator?
Arthur C. Clarke introduced it to the general public in "The Fountains of Paradise", although it is an idea from a Russian scientist...
What about Jack and the beanstalk, what kind of genetic engineering and mechanical engineering is required to have a plant grow as long as to reach the sky?
Not to metioned the speed and materials required to make it grow over night!