Dormant Siva Cluster Use. The dormant siva cluster is on the metal arm hanging from the ceiling. Unusually, this dormant siva cluster is in a social space.

15 easy siva dormant cluster locations walk through! The dormant siva cluster is on the left side of the room in a locker. This dormant siva cluster can be found while completing the final story mission for rise of iron, “the iron tomb”.
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Head into the ketch and up the stairs on the left. You will need to use the surrounding scaffolding to reach it. Credit to /u/soundwave5150 for finding this one.
Based On What Happened When Players Collected 45 Out Of 50 Calcified Fragments, There Could Be Something.
I know there's been a few of these threads, but none of them are complete, or they are out of order like the megathread. In this room is the dormant siva cluster. Climb the rocks to the right of the bridge, and jump down the ledges.
They Can Be Found All Throughout The Game World In Places That Have Been Updated By The Rise Of Iron Expansion.
Credit to /u/ladyalastor for this find. Where the walker is, go into the room on the left and open it with the splicer key. This cluster is located in a nook right after the siege engine boss fight.
Once You Jump Down From The Wall, You’ll End Up On A Rocky Island With A Bridge Leading Away.
Once you reach the divide, head over towards dock 13 as if you were heading back to the steppes. This dorman siva cluster can be grabbed from behind the monitor. There is no known reward for collecting all 30 dormant siva clusters.
On Top Of The Tower Is Dormant Siva Cluster Fallen 3.0.
This next dormant siva cluster can be found in the refinery a location that connects the rocketyard to the blast where you fight sepiks prime. Once you have a splicer key, start up the plaguelands and head from the rocketyards towards the blast (where you'd go for the sepik's strike). The dormant siva cluster is located on the broken bridge, jump from the cylinder to grab it.