Robust glass is a thick type of glass used for creating potion flasks. It is created by melting red sandstone in a robust glass machine, which can be found southwest of the mud bath in Oo'glog or by the pottery oven in the Ithell district of Prifddinas. The machine requires completion of As a First Resort to use.
Melting red sandstone has no skill requirements, but creating potion flasks from robust glass requires level 89 Crafting and gives 100 Crafting experience. This requirement can be boosted, but it cannot be assisted. Strange and golden crafting rocks can be obtained from creating potion flasks.
|Completed As a First Resort|
|Item quantity required||1|
|Base junk chance||98.9%|
- An update in May 2017 changed the colour from purple to yellow in the inventory, but the dropped item remains purple.