Coins and the Dynamic Market

Bronze, Silver and Gold Coins are OceaniaRO's second currency. Almost everything the Tidemark Company pays you is denominated in them, and the place to spend them is the Dynamic Market in Prontera.
The Dynamic Market
Where: Prontera, 155 / 183 — just north of the fountain.
The Market buys and sells a fixed list of crafting materials, consumables and upgrade materials. Prices are not fixed. They move with what the whole server has been doing that day.
Every 5 purchases of an item raise its price by 1 coin.
Every 10 sell-backs lower it by 1 coin.
Price can never fall below half the base, or rise above three times it.
Everything resets at midnight.
Selling back pays 50% of the current buy price, and pushes that item down for everyone — so a server that farms Oridecon hard makes Oridecon cheap. The Demand Report option shows what has been moving.
Bronze tier — crafting materials
Item
Base price
Iron
3 Bronze
Steel
5 Bronze
Elunium
4 Bronze
Oridecon
4 Bronze
Phracon
2 Bronze
Trunk
2 Bronze
Emveretarcon
4 Bronze
Silver tier — consumables
Item
Base price
White Potion
2 Silver
Blue Potion
3 Silver
Speed Potion
4 Silver
Box of Thunder
5 Silver
Anodyne
2 Silver
Aloebera
2 Silver
Gold tier — upgrade materials
Item
Base price
Enriched Oridecon
5 Gold
Enriched Elunium
5 Gold
HD Oridecon
8 Gold
HD Elunium
8 Gold
Carnium
10 Gold
Bradium
10 Gold
HD Carnium
15 Gold
HD Bradium
15 Gold
Base prices are the starting point, not what you will pay. Check the live menu.
Exchange rates
The Market converts coins in both directions. Going up the ladder is free. Coming back down costs a 10% fee, on purpose — it stops coins being cycled for profit.
Up — no fee
Down — 10% fee
50,000 Zeny → 1 Bronze Coin
1 Bronze Coin → 45,000 Zeny
5 Bronze → 1 Silver
1 Silver → 4 Bronze
5 Silver → 1 Gold
1 Gold → 4 Silver
So one Gold Coin is 25 Bronze, or 1,250,000 Zeny if you buy it outright. Earning coins is almost always cheaper than converting for them.
Where coins come from
Tidemark Bounty Board — 2 / 4 / 6 Bronze by bounty tier, plus a standing bonus.
Lore Story Quests — every chapter pays Bronze; finishing all five adds a 10 Bronze bonus.
The Choir Roster and Signs on the Tide — Bronze on completion, and the Saltwalker sells hints for a single coin.
Poring Haven — Crown Couriers and Tide Couriers carry Bronze; rally milestones pay out at 50 / 150 / 400.
The Sundered Forge — Bronze alongside Red Blood and Burning Hearts.
Your Harbor Reputation changes these payouts — Marine rank and above add Bronze to bounties, and Saltwalker discounts what the Company charges you.
Related pages
Harbor Reputation
Tidemark Bounty Board
Tidemark Company Mercenaries