The Sea Treasures collection log in Old School RuneScape is a Sailing-related completionist activity consisting of 17 total log slots. It combines long-term RNG-based salvaging with a set of relatively quick exploration with OSRS gold and interaction tasks across multiple islands.

Requirements and Core Structure
To fully complete the log, players must obtain:
· Eight medallion fragments
· The Sailor’s Amulet
· One unique item from each salvaging location
The salvaging uniques are the primary time sink, with an estimated drop rate of around 1 in 3,000 salvages. Due to high variance, completion can range from a few thousand to well over 7,000+ attempts. The guide recommends progressing salvaging passively while training Sailing rather than treating it as a standalone grind.
Each unique salvaging item is turned in at the Varrock Museum, granting Kudos and an experience lamp that can be used on any skill, often Sailing for additional progression value.

Medallion Fragment Locations
The eight medallion fragments are significantly faster and are obtained through diverse island activities:
· Dognose Island: Pick a locked chest repeatedly until the fragment drops.
· Great Conch (Coral Reef): Dive with fishbowl helmet and apparatus, then investigate the reef.
· Onyx Crest Pirates: Obtain via pickpocketing (60 Thieving) or killing pirates.
· Atrocious Island: Offer fruit to a raccoon in the northern area.
· Port Roberts: Steal from the silver stall in the market.
· Shimmering Atoll: Chop a teak tree to instantly receive the fragment.
· Isle of Bones: Investigate a cauldron for the fragment.
· Crab Monument: Sail and chart the location to unlock the final fragment and Crab Dance emote.

Assembling the Medallion of the Deep
After collecting all fragments, players must obtain the Waterlogged Journal from a crate in the Pandemonium bar. Reading it enables combination of all fragments into the Medallion of the Deep.
This item allows underwater exploration without diving gear, improving inventory flexibility. It is also required for a Master Treasure Trail step and remains useful for activities like coral farming.

Conclusion
The Sea Treasures log blends a long RNG-heavy salvaging grind with fast, varied exploration tasks. While salvaging uniques represent the primary bottleneck, the medallion fragments with cheap RS gold provide a quicker and more engaging progression path. With consistent effort during Sailing training, players can eventually complete all 17 entries and earn a distinctive endgame reward.