Fake Rock help

[Jungletrans]

Not wanting to pay $100 for a fake rock hide l am building my own . Paper mache over a plastic bag of rags gave me the right size and shape . Now it is dry l need to seal it with something . Anyone done this before ? Some sort of render or whatever will dry like rock . l guess its off to Bunnings .

[fuegan13]

i used sand cement for mine.... you can put colours in it to make it more rock like and it has a nice sandstone like texture..... you can seal over the top of it as well...

[Fuscus]

tile grout and paint

[jbourke]

Pics?

[angel_saza]

i've used tile grout and acrylic paint before, but that was over polystyrene foam. Also have a fake rock in the making and i've used expanding foam. I'll be using tile grout for this too. Make sure you seal it too... i've used pond sealer in the past, but it gives a glossy finish.