Doesn't matter which type of glass it is. mostly they are some kind of borosilicate glass with some additions and protecting layers.
Most important thing to know is which wavelength your laser is emitting and if this wavelength is absorbed by the material of interest. As we all know, glass is usually transparent to visible light (range of 400-800 nm wavelength). So if your laser uses also visible ligth, your etching wont be successfull. Etching with a laser only works, if the light of laser gets absorbed. Thus the energy of the light gets transformed to heat and by that laser ablation works.
look at that graphic for a special borosilicate glass (pyrex) http://www.pgo-online.com/intl/katal...rex_kurve.html
reading this, your laser should be far in the uv light (lambda < 200 nm) or far in the infrared (lambda > 3500 nm)
Edit: I just had a quick search on the gorilla glass. here is some kind of datasheet: http://www.corninggorillaglass.com/s...t%20010713.pdf
Here you can also find a transmission spectrum (here it is for gorilla glass 3, but should be valid for gorilla glass 2, too). Looks similar to the one behind the link I posted. so the conclusion remains.
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