Cut a Gem is a Roblox incremental game built around one simple engine that keeps scaling. You buy raw geodes, grind them into gems on your plot, and sell those gems to buyers who pull up on a conveyor belt. Everything you earn feeds back into faster grinders, luck and money totems, and eventually a rebirth that resets your cash for permanent bonuses. You can jump into Cut a Gem directly and start with the free Basic Grinder.
Quick answer: Buy a geode, place it in a grinder to turn it into a gem, drop the gem on your conveyor and accept a buyer’s offer, then reinvest the cash into faster grinders and totems until you can pay the $1,000,000 first rebirth for permanent money and grind-speed multipliers.
The grinding loop, from geode to sale
The whole game runs on a five-part cycle that never really changes, only speeds up. Learn it once and every upgrade afterward makes sense.
Grinders and their speed and purity bonuses
Grinders are the single most important upgrade in the game. A faster machine cuts processing time and adds purity, which raises how much each gem is worth. The difference is dramatic. A Dark Mudstone geode takes 12 hours on a Basic Grinder but only 6 hours once you equip a Power Buffer. Speed multipliers stack up quickly as you climb the ladder.
| Grinder | Cost | Speed / Purity |
|---|---|---|
| Basic Grinder | $1k | Normal speed and purity |
| Power Buffer | $21k | 2x faster, +22% purity |
| Hydro Glazer | $440k | 4x faster, +43% purity |
| Laser Cutter | $25.5M | 8x faster, +51% purity |
| Plasma Shiner | $1B | 16x faster, +53% purity |
| Quantam Aligner | $250B | 32x faster, +55% purity |
| Ultrasonic Crusher | $10T | 64x faster, +56% purity |
The practical rule is to buy the next grinder tier before you buy anything decorative. Speed compounds, so upgrading every active tile matters more than hoarding cash. Grinders also keep running while you are offline, but only if geodes stay queued and finished gems get collected, so a faster machine finishes more offline cycles within the cap.
Tip: Higher purity is not just a stat. It directly raises the price a buyer offers, so a purity jump pays for itself as soon as you sell a few gems.
Totems that boost value, size, and speed
Totems add passive bonuses that multiply your income without changing the core loop. Growth totems make gems physically bigger, and heavier gems sell for more. Others increase how much customers pay or speed up grinding on a chance-based roll. Place totems before buying new grinders so fresh machines benefit from the buffs right away.
| Totem | Cost | Effect |
|---|---|---|
| Small Growth Totem | $250k | 15% chance to grow a gem, +15% bigger |
| Medium Growth Totem | $50M | 30% chance to grow a gem, +30% bigger |
| Big Growth Totem | $1B | 50% chance to grow a gem, +60% bigger |
| Increase Rich Customer | $12M | 30% chance a customer pays +20% more |
| Grinder Speed Totem | $5B | 50% chance a grind finishes 5% faster |
| Radioactive Totem | $5B | 8% chance a gem turns radioactive (2.5x value) |
Note: Rebirthing raises your maximum totem count, so the early Small Growth Totem is worth grabbing even though better ones exist later. There is a hard cap on how many you can place at once.
Displays and decor
Displays let you show off a single gem, and the higher tiers make the displayed gem more valuable over time. Decor items are purely cosmetic for your plot. Neither should come before grinders or totems in your spending order, but the displays do earn passive value once your cash flow is comfortable.
| Item | Cost | Type |
|---|---|---|
| Basic Display | $1M | Displays one gem |
| Gold Display | $1B | Displayed gem gains value over time |
| Diamond Display | $1T | Premium display |
| Traffic Cone | $50k | Decor |
| Sunflower | $150k | Decor |
| Caution Board | $750k | Decor |
| Bench | $2.5M | Decor |
| Lamppost | $2.5M | Decor |
| Flower Pot | $5.5M | Decor |
Geodes and the gems they produce
Two shops sell your raw materials. Jake’s Geode Shop carries standard rocks, while Tammy’s Dark Geode Shop stocks heavier Dark geodes that take longer to grind but sell for much more. Pricier geodes are only worth buying once your grinder can process them in a reasonable time, so match your geode tier to your machine.
| Geode | Cost | Shop |
|---|---|---|
| Cobblestone | $50 | Geode Shop |
| Mudstone | $550 | Geode Shop |
| Sandstone | $5.8K | Geode Shop |
| Granite | $63K | Geode Shop |
| Dark Mudstone | $1.8K | Dark Geode Shop |
| Dark Granite | $200K | Dark Geode Shop |
Standard geodes tend to produce colored crystals such as the Dull Crystal, Yellow Crystal, and Red Crystal. A higher-tier geode plus a high-purity grinder is what pushes single sales into the tens of thousands and beyond.
Rebirths: what the first reset gives you
Rebirth is the long-term progression system. It wipes your cash and grinders in exchange for permanent multipliers that make your next run far faster. The first rebirth costs $1,000,000, and the bonuses apply to everything you do afterward.
| Rebirth | Cost | Benefits |
|---|---|---|
| Rebirth 1 | $1M | 1.25x Money, Max Totem 15, 1.15x Grinder Speed |
Because a rebirth resets your machines, do not sink money into your grinder line right before pulling the trigger. Save toward the $1,000,000 threshold, rebirth, then immediately rebuild your grinders using the retained multipliers so the money and speed bonuses start working at once. Skipping straight back into higher-tier grinders after a reset is faster than grinding from the Basic Grinder again.
Daily rewards and the free spin
Log in each day to claim a login reward. The Day 1 reward alone is $10,000, which is a huge head start early on. You can also spin a free prize wheel once every 24 hours for a chance at premium gear. It is possible to win machines like the Power Buffer from a spin, effectively skipping a paid upgrade.
Working codes and how to redeem them
Codes give free cash and temporary boosts. They are case-sensitive, so type them exactly or paste them to avoid typos and trailing spaces.
| Code | Reward |
|---|---|
| RELEASE | 1,000 Cash |
| GEM | 2x Gem Profit Boost (15 minutes) |
| CUT | Free Speed Boost |
Put together, the fastest route through Cut a Gem is to keep your grinders one step ahead of your geodes, layer in growth and value totems before each new machine, claim your daily login and spin, and time your first rebirth for the moment you hit $1,000,000 so the permanent multipliers carry your next run.
