Horizon Zero Dawn has 30 Metal Flower Locations. Finding all of them unlocks the trophy "All Metal Flowers found" [Bronze]

You can buy a map for their general areas at any merchant. This doesn't give you the exact location, only a rough search area. Press R3 to scan for the flowers. Then pick them up.
After finding all 30 you can bring them to the collectible merchant in Meridian to receive 3000 Metal Shards and several purple Modifications. Each Metal Flower has its own unique name which you can look up in the Notebook (press Touchpad). There you can also see how many you've found.

The collectibles are not saved automatically. Meaning you must reach a checkpoint or campfire to save the progress. None of them are missable, can get everything in free roam after story.

TIMELINE:

#1 - Mark I (B) - 0:05
#2 - Mark I (A) - 0:39
#3 - Mark I (C) - 1:27
#4 - Mark I (F) - 1:45
#5 - Mark I (D) - 2:11
#6 - Mark I (E) - 2:29
#7 - Mark I (G) - 2:47
#8 - Mark I (H) - 3:08
#9 - Mark I (I) - 3:25
#10 - Mark I (J) - 3:40
#11 - Mark III (C) - 4:00
#12 - Mark II (B) - 4:23
#13 - Mark II (A) - 4:44
#14 - Mark II (E) - 5:00
#15 - Mark II (C) - 5:15
#16 - Mark III (J) - 5:35
#17 - Mark III (H) - 5:50
#18 - Mark III (I) - 6:06
#19 - Mark III (B) - 6:33
#20 - Mark III (A) - 6:47
#21 - Mark III (F) - 7:06
#22 - Mark III (D) - 7:49
#23 - Mark III (E) - 8:09
#24 - Mark III (G) - 8:52
#25 - Mark II (J) - 9:05
#26 - Mark II (I) - 9:20
#27 - Mark II (H) - 9:53
#28 - Mark II (D) - 10:11
#29 - Mark II (F) - 10:34
#30 - Mark II (G) - 10:54

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