Hydroneer Gem Values: Emerald, Ruby, Sapphire, Onyx & Diamond Prices

You just hauled a diamond out of the dirt and you have no idea whether it's a fortune or pocket change. That's exactly why Hydroneer gem values matter: the number attached to an item is not the number a buyer pays until weight, polishing, and the right buyer are all baked in. Below you'll find the community-recorded Hydroneer gem values for every gem in the game, each tied to the date it was captured, along with the weight math, spawn odds, and selling spots that turn a raw find into real coin.

How Hydroneer Gem Values Are Calculated

In Hydroneer, a sale price is never one fixed number. Each resource type carries a base value, and each individual lump you dig up carries its own weight, which acts as a multiplier on that base. Know both numbers and you can estimate a payout before you carry anything to a buyer.

Rainrune's Hydroneer Price Guide on Steam Community states the relationship as price ÷ base value = weight, which in plain terms means sale price = base value × weight. A weight-2 chunk of iron against a 10c base works out near 20c; the same chunk at weight 0.5 lands closer to 5c.

One caution before you trust any formula: commenters on that same guide point out that two of its rearranged equations have their operators flipped, and the author openly admits the math section may be off. Trust the single relation above and let the game confirm it for you.

The fastest verification happens in your own save. In a March 2021 Steam discussion about ore and gem values, ItchyBeard — who maintains the Bridgepour wiki — told players to press B while looking at an item to read its value directly. As of 2026-11-14, the Bridgepour wiki's emerald entry still hosts a weight:value converter, so that advice holds.

The Recorded Base Values for Gems and Ores

The table below gathers the recorded Hydroneer gem values alongside ore prices for context, so you can see how a gem compares to the metal you're already smelting.

All values above: Rainrune's Steam Community Hydroneer Price Guide, posted June 11, 2024, page snapshot captured 2026-11-14. Community-recorded figures rather than developer-confirmed ones; metal rows are unrefined, gem rows are refined.

Two modifiers sit on top of those numbers, per the same guide: refined metal sells for about 30% more than unrefined metal, while unrefined gems sell for about 70% less than refined ones. That makes polishing the single biggest lever on a gem's payout — far more important than squeezing out a slightly heavier stone.

Polishing, Refining, and the 70% Penalty

Gems come out of the dirt uncut, and the Hydroneer 2.0 beginner guide is blunt about the fix: you either polish gems by hand or automate the job with a gem polisher belt hook. Skip that step and you're selling the discounted, unrefined version of every stone.

Apply the guide's stated 70% reduction literally and an uncut emerald lands somewhere near 6–7c instead of the listed 22c. The exact figure still moves with the piece's weight, so treat that as arithmetic on the guide's own rule rather than a confirmed in-game number.

Refinement matters beyond gems, too. The beginner guide warns players to keep smelting lines single-metal — iron in one crucible, gold in another, cloutium and power shards in their own — because mixing ores wastes valuable material. From there the crafting chain runs crucible → mould → furnace → anvil, with a blacksmithing hammer for the final step.

Spawn Chances: How Often Gems Actually Show Up

Raw Hydroneer gem values only pay off if you can find the stones, so the drop rates matter as much as the prices.

Spawn chances from Rainrune's Steam Community Hydroneer Price Guide, posted June 11, 2024, page snapshot captured 2026-11-14. The guide author could not find rates for diamond or hardstone and left them out rather than guess.

Gems account for roughly 4.9% of drops in the guide's sample, so about one find in twenty. The missing diamond and hardstone rows are a useful reminder that community data has gaps — if a number isn't listed, the honest answer is to check your own results rather than assume.

Two extra details fill in the picture. The Bridgepour wiki labels its spawn table as tier-3 data, so those odds describe tier-3 digging specifically. And the beginner guide notes that deeper dirt holds better-grade material, while the starter Forged Iron drill is rated for tier 1 dirt — so chasing higher-value stones usually means digging down and improving your drill.

Where to Sell Gems and How to Protect Your Profit

As of 2026-11-14, the Bridgepour wiki's emerald entry lists three outlets: the Jeweller in Bridgepour, the Jeweller at Bastion Keep, and the Stock Market in Icehelm. Those are the documented gem buyers, and they're where the selling half of Hydroneer gem values actually gets realized.

The beginner guide adds that crafting beats raw selling. Rings, necklaces, daggers, and swords can be worth more than bars or nuggets, and jewelers and the stock exchange pay well for finished pieces. A polished emerald therefore has two exits: sell the stone outright, or turn it into jewelry first and capture the markup.

A short checklist keeps the math on your side:

• Polish before you sell. The 70% unrefined penalty dwarfs most weight gains.
• Read the weight, not the picture. Press B on any item to see its true value before loading the truck.
• Split your lines. The beginner guide recommends conveyor splitters so gems, iron, gold, and cloutium never share a crucible.
• Verify in your own save. Steam even displays an incompatibility warning on the guide page, so treat its figures as a starting point, not gospel.
• Compare outlets. A jeweler that buys the stone and a stock exchange that buys the finished ring are two different paydays.

FAQ

What are the highest Hydroneer gem values? Onyx and diamond tie at 250c each in Rainrune's Steam Community price guide, posted June 11, 2024 and snapshot-captured 2026-11-14 — roughly ten times the 22c listed for an emerald. Neither has a published spawn rate in that source.

How much is an uncut gem worth? The guide lists polished figures only and states that unrefined gems are worth 70% less. Applying that rule to an emerald puts an uncut stone in the 6–7c range before weight is factored in. Press B in-game for your specific piece.

Do Hydroneer gem values change between updates? They can. The figures here are a dated community snapshot, not a live feed, and the guide page even carries a Steam incompatibility warning. Check the in-game value readout or the wiki calculators before you plan a big sale.

Where do you sell gems in Hydroneer? Community documentation points to the Jeweller in Bridgepour, the Jeweller at Bastion Keep, and the Stock Market in Icehelm. Crafting a ring or necklace first usually beats selling the raw stone.