Below is a guide on the location of the containers found throughout the Keves Castle Region in Xenoblade Chronicles 3.
Syra Hovering Reefs
Nopon Coin (Silver) x2
Near the Penshia Portal landmark
Pure Gemstone, Utility Gloves
Southeast of Penshia Portal landmark just outside Colony 11
Nopon Coin (Silver) x5
Colony 11 – Northern side of the colony
Pure Gemstone
Colony 11 – In a storage container on the south side of the colony
Pure Gemstone x2, Strung Amber
Colony 11 – In a storage container next to the canteen
Nopon Coin (Silver) x5
Hovering Reef 6 – South of Penshia Portal
Pure Gemstone, Circadian Tea
Hovering Reef 5 – South of Penshia Portal landmark
Pure Gemstone x3, Fierce Armor Vest
Hovering Reef 4
Nopon Coin (Silver) x2
Hovering Reef 2
Nopon Coin (Silver) x2
Hovering Reef 1
Ironclad Undershirt, Pure Gemstone x1
Ether Mine
Pure Gemstone x2, Nacre Choker
Hovering Reef 1
One-Cup Liquid Grub, Pure Gemstone
Southeast of Ekdaso Verge landmark
Nopon Coin (Silver) x2
West of Great Sword Furrow landmark
???
Fourth Ixia Bridge – Northwest of Ekdaso Verge landmark – Guarded by Level 64 unique enemy
Ultra Pure Gemstone
Gardin Defense Base – You’ll come here during the Side Story: Noah hero quest; atop a tower
Ultra Pure Gemstone x2, Victor Gauntlet
Gardin Defense Base – You’ll come here during the Side Story: Noah hero quest; in a storage container
Nopon Coin (Gold)
Gardin Defense Base – You’ll come here during the Side Story: Noah hero quest; In the Tap-Dancing Nopon rest spot
Induction Bangle, Ultra Pure Gemstone x3
Holy Lid – Climb the long ladders in Fort O’Virbus
Nopon Coin (Silver) x2
Fort O’Virbus – Southeast of East Gate Road
Ultra Pure Gemstone
Fort O’Virbus – In a room southeast of the West Gate Road landmark; area is reachable after The True Inspector standard quest
Lustrous Armring, Ultra Pure Gemstone x3
Fort O’Virbus – On the roof directly east of The Tap-Dancing Nopon rest spot. To reach it use the ladders on the northern side of the area to reach the Holy Lid secret area then drop down to the roofs containing the container.
Ultra Pure Gemstone x2, Harness Belt
Fort O’Virbus – On the roof directly northeast of the West Gate Road landmark. To reach it use the ladders on the northern side of the area to reach the Holy Lid secret area then drop down to the roofs containing the container.
Keves Castle
Pure Gemstone x2, Eraser Orb
Castle 1F- Hangar, Lower Level – Southwest of Storage Area #1
Nopon Coin (Silver) x2
Castle 1F- Hangar, Lower Level – Northwest of Storage Area #1
Nopon Coin (Silver) x5
Castle 1F- Storage Area #2 – At landmark
Pure Gemstone
Castle 1F- Storage Area #2 – Just south of landmark
Pure Gemstone
Castle 2F – Storage Area #3
Nopon Coin (Silver) x2
Castle 2F – Hangar, Lower Level
Pure Gemstone x3, Dragonfang Necklace
Castle 2F – Hangar, Lower Level – Just northwest of the Storage Area #3 landmark; move the northeastern loading dock to reach it
Repulsor Cuffs, Pure Gemstones x2
Castle 3F – Standby Room #1 – Northwest of Troop Reserve Section
Nopon Coin (Silver) x5
Castle 3F – At the Equipment Storage landmark
Pure Gemstone
Castle 3F – Northeast of Annihilator Foundations landmark behind raising platforms