After you beat Oryx, you get a BUNCH of quests back at the tower. one of which involves collecting 25 Hadium Flakes and 10 motes of light. The motes are a joke, but the Flakes can take a bit. If you are a NightStalker ( you are super awesome like me) you have the Keen Scout perk which makes this a breeze. having all the materials and chests show up on your minimap is incredible. The best place to do this is in the starting area of patrol. There are about 4-6 Chest locations and spawn pretty rapidly. There was never a time I went around the entire room and didnt get a chest.

ProTip: Be a Nightstalker, and just gather 75 or just gather on Nightstalker for your other classes. Alternatively, join up or follow a Nightstalker. There was a random guy following me around the area because he knew that I had Keen Scout.

The whole process might take about 30-45 mins, but you get a sword out of it!