Will It Support?

[rosiew]

Morning.
We have a fire that sits on a glass shelf inside a Marble Fire surround, we are in the middle of changing the gas fire and the new fire weighs considerably more. Im worried that the new fire may be too heavy. Can glass support a lot of weight.

[buildersmate]

This is a how long is a piece of string question. There is greenhouse glass that is thin and whose purpose is to transmit maximum light through and there is toughened glass that withstands huge forces at, for example, the viewing area at the bottom of an underground aquarium.
You are not going to be able to describe this adequately to get a sensible answer here.
Best bet is to technical advice from the organisation supplying and fitting the fire.