Gems in Ultimate Mining Tycoon
Gemstone types, depths, and jewelcrafting chain reference.
Gems (gemstones) spawn alongside ores in The Mine, concentrated in Crystal Depths and deeper Underworld layers. Unlike metal ores processed through furnaces, gems route through jewelcrafting machines — Gem Cutter, Polisher, and advanced assemblers — on a parallel factory spine separate from your main metal belt.
Mine alongside ores using the same pickaxes — Diamond Pickaxe ($2.5M) mines all gems. Depth context: Mine Layers and Ores.
Gem vs ore: key differences
| Property | Ores | Gems |
|---|---|---|
| Primary chain | Furnace → Stamper | Gem Cutter → Polisher |
| Typical depth | All layers | Crystal Depths+ |
| Inventory slot | 1 per gem | 1 per gem |
| Mixing on belts | Causes jams early | Keep separate spines |
| Pickaxe requirement | Strength-gated | Diamond mines all |
Never merge gem and ore on one conveyor until you operate advanced sorting — Factory Layout.
All 10 gems (base values)
| Gem | Base value | Strength | Depth band (approx.) |
|---|---|---|---|
| Topaz | $75 | 6 | 0–549m |
| Emerald | $200 | 14 | 150–849m |
| Sapphire | $250 | 14 | 150–849m |
| Ruby | $300 | 18 | 150–849m |
| Diamond | $1,500 | 22 | 400–1800m |
| Poudretteite | $1,700 | 75 | 550–1199m |
| Zultanite | $2,300 | 110 | 1000–1599m |
| Grandidierite | $4,500 | 120 | 1400–2100m |
| Musgravite | $5,800 | 150 | 1900–2900m (v0.5.5+) |
| Painite | $12,000 | 200 | 2100–4500m (v0.5.5+) |
Strategy walkthrough: Gems and Jewelcrafting. Cut and polish before selling raw.
Jewelcrafting machine chain
[Gem Unloader branch] → Gem Cutter → Gem Polisher → [Jewel Assembler] → Sell PointMachine tiers: Machines Tier List — jewel branch rated A-tier mid-game, S-tier when fed consistent Crystal Depths hauls.
Build this spine beside your metal Furnace row, not downstream of it.
Mining gems efficiently
- Depth target — Farm Crystal Depths (~1,900m – 2,300m) once Steel/Diamond pickaxes access it.
- Inventory discipline — Fill backpack with gems + matching high-tier ores; avoid Tin pollution.
- Vehicle capacity — Same rules as ore: Super Crawler 180 slots.
- Crystalline hitboxes — v0.5.0 switched crystalline ores to box hitboxes; gems register pickaxe hits more reliably now.
- Explosives caution — Do not nuke gem clusters when clearing stone — collateral gem destruction wastes value.
Gem + ore dual haul strategy
Advanced players run dual unloaders — one metal, one gem — fed by sorted mining trips. Mid-game players should dedicate entire trips to gems OR ores, not both, until factory supports split belts.
Sell value optimization
| Stage | Relative value |
|---|---|
| Raw gem pickup | Baseline |
| After Gem Cutter | Moderate multiply |
| After Polisher | High multiply |
| After Jewel Assembler | Maximum |
Raw gem selling is acceptable only before first Gem Cutter purchase — then processing always wins.
Prestige and gems
Ore Upgrader affects ores only, not gems. Gem routes persist unchanged after prestige — rebuild jewel spine alongside metal chain. Medals better spent on pickaxe upgrades for faster gem mining — Prestige Upgrades.
Persistence
Gems in backpack, vehicle, and unloader save on logout like ores. Ore Recovery Centre handles mixed inventory recovery.
Related pages
- Ores Reference — metal counterpart
- Equipment — Diamond pickaxe milestone
- Items Hub — all resources
- Gems and Jewelcrafting — full routing guide
- Early Game Money — when to invest in gem machines
Gems reward players who build a second factory spine — ignore them and you leave Underworld money on the mine floor.
Frequently Asked Questions
Quick answers to the most common questions.
Where do gems spawn?
Primarily in Crystal Depths (around 1,900m–2,300m) and deeper Underworld layers alongside crystalline rock formations.
Do gems use the same machines as ores?
No. Gems use jewelcrafting machines like Gem Cutter and Polisher, not Furnaces.
Which pickaxe mines all gems?
Diamond Pickaxe ($2.5M) is the first pickaxe that mines every ore and gem in the game.
Should I sell raw gems?
Only before you build a Gem Cutter. Processed gems sell for significantly more.
Does Ore Upgrader affect gems?
No. Ore Upgrader transmutes ores one tier higher. Gems follow a separate processing chain.