Optic Glass is a Rare crafting material used for a handful of Contracts in The Cycle: Frontier. However, this particular material is far more relevant for its second use: to craft scope attachments for weapons. If you are struggling to find enough Optic Glass in The Cycle: Frontier, this guide should help you farm up quick and make all the scopes you want.
As in-game tooltips would tell you, Osiris facilities tend to have Optic Glass lying around. However, they are not the only source of this material. Any science outpost on either map in The Cycle: Frontier has a chance to spawn Optic Glass, but the most consistent way to find some is by visiting three particular locations on the Bright Sands map. The first one is the Waterfall Lab located in the northeast corner of the map. The second is Vaccine Labs, which can be found near the equatorial middle of the eastern fringe of Bright Sands. Both places are PvP hot zones, so be careful.
If you want to avoid fights, the third spot to find Optic Glass in The Cycle: Frontier is the observation tower near Rock Pools, which is located right next to an extraction zone in the lower western quadrant of the map. At worst, there may be an ambusher waiting at the tower with a sniper rifle, but if you make it there without issues you are in the clear. You won’t find a lot of Optic Glass there (one or two pieces at the most) but you also won’t be putting yourself at any serious risk.