3D Gem Placement & Yield Optimization

Cut more stone.
Waste less rough.

gemjacket uses volumetric signed-distance-field analysis to find the mathematically optimal orientation, position, and scale for any gem design inside any piece of rough — so you maximize yield before a single facet is ground.

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No credit card required. Start with 3 free optimizations per month. View all plans →

±0.1°
Rotational Accuracy
Sub-mm
Containment Precision
STL
Industry-Standard Format
1000+
Designs in Library
Core Capabilities

The full pre-cutting workflow
in a single browser-based tool

From 3D rough scan to printed dop jig — gemjacket replaces guesswork with mathematics at every step.

Volumetric Yield Optimizer
Upload a 3D scan and gemjacket converts it into a high-resolution signed distance field, then searches thousands of orientations across all three rotational axes to find the placement that yields the largest possible gem — sub-millimeter precision, every time.
SDF Engine
Multi-Gem Placement
Fit multiple gems into a single rough with proportional placement. Each stone is sized to maintain similar proportions relative to the available volume, so you get a balanced suite of gems rather than one oversized stone and diminishing leftovers.
Multi-gem
3D Gem Import
Load gem designs from STL files — the industry-standard 3D mesh format exported by every major gem design tool. The importer auto-validates geometry, repairs normals, and extracts facet metadata.
STL Import
Dop Sheet PDF Export
Generate a printable dop instruction sheet with precise contact point coordinates, dop axis vector, angle from vertical, recommended dop diameter, estimated crown height, and full placement data — ready for the cutting bench.
PDF Export
3D-Printable Alignment Jig
Download a custom STL jig sized to your dop rod and angled to match the computed dop axis. Print on any FDM printer, insert the dop and rough, and let the cement cure with the stone at exactly the right orientation — hands-free, zero guesswork.
Jig STL
Gem Design Library
Browse a curated library of gem designs — searchable by shape, designer, symmetry, aspect ratio, and refractive index. Upload and share your own designs with the community, or keep a private collection. Auto-recommendation matches designs to your rough geometry.
Library & Community
Workflow

Three steps from rough to cut plan

01
Upload your rough
Upload an STL scan of your rough stone. gemjacket converts it into a volumetric signed distance field — a 3D grid that maps every point inside and outside the stone to sub-millimeter precision. Or enter L × W × H for a parametric box.
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02
Choose gem designs
Select from the built-in design library or upload your own gem design as an STL file. Queue multiple gems for multi-stone placement. Use table-lock mode for pleochroic materials where color orientation matters.
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03
Optimize & export
The engine tests thousands of orientations, finds the maximum scale at each, and returns the best placement. Export the dop sheet PDF, 3D-printable alignment jig, and placed gem STL — everything the cutter needs to start grinding.
Included Tools

A complete lapidary pre-cut toolkit

Every tool runs in the browser. No installation, no plugins, no desktop software.

◈
SDF Placement Engine
Converts your rough into a volumetric signed distance field, then searches thousands of orientations across all three rotational axes. Two-phase search: global sampling then local refinement.
⟳
Binary Scale Solver
For each candidate orientation, binary search converges on the maximum gem size in ~60 iterations — checking every surface point simultaneously. Sub-millimeter precision guaranteed.
◉
Table-Lock Mode
Fix the gem's table facet to a specific crystal axis for pleochroic materials — sapphire, tourmaline, Oregon sunstone. Controls which color the finished stone displays through the table.
◆
STL Importer
Import gem designs from STL files — the standard format exported by GemCAD, GemCut Studio, and other design tools. Auto-validates geometry, repairs normals, and extracts facet metadata.
▣
Dop Target Calculator
Computes the precise dop attachment point by raycasting along the planned axis. Outputs contact coordinates, axis vector, vertical angle, dop diameter, and crown height.
⬡
Jig STL Generator
Generates a 3D-printable alignment jig with a hole sized to your dop rod and angled to match the computed axis. Print on any FDM printer for hands-free dop cement curing.
◌
Manual Placement
Click-drag the gem in the 3D viewer to position it by hand. Real-time containment checking confirms every surface point stays inside the rough as you move.
▤
Rough Box Creator
Enter L x W x H in millimeters to create a parametric box rough — ideal for calibrated synthetic material, rectangular slabs, and native cuts. Full optimizer pipeline applies.
Pricing

Plans that scale with your bench

Start free with real rough. Upgrade when you need more runs, exports, or team features. Annual billing saves ~14%.

Free
$0/mo

Evaluate gemjacket with real rough — no credit card, no time limit.

  • 3 optimizations per month
  • 1 gem per optimization
  • 5 gem library uploads
  • Community library browsing
  • STL import
  • Table-lock / multi-gem
  • PDF & jig exports
Get Started Free
Hobby
$9/mo

For hobbyists who cut a few stones a month and want the full optimizer.

  • 30 optimizations per month
  • Up to 3 gems per run
  • 25 gem library uploads
  • Table-lock mode
  • Multi-gem placement
  • Community upload & voting
  • PDF & jig exports
Start Hobby Plan
Pro
$29/mo

For working lapidaries who need unlimited runs and full export capability.

  • Unlimited optimizations
  • Unlimited gems per run
  • PDF dop sheet export
  • 3D-printable jig STL
  • Priority compute queue
  • 200 library uploads / 1 GB storage
  • Full design library access
Start Pro Plan
Studio
$79/mo

For gem studios, schools, and commercial operations needing batch & team.

  • Everything in Pro
  • Batch optimization runs
  • Team seats (up to 5)
  • API access for integrations
  • Unlimited uploads & storage
  • Priority support
  •  
Start Studio Plan

All plans billed monthly. Save ~14% with annual billing — contact us.
Stripe-secured payments. Cancel any time. Enterprise & B2B volume pricing available — get in touch.

Company

Built by cutters,
for cutters

gemjacket was built to solve a real problem: figuring out how to orient rough stone for maximum yield before the first facet is ground. Traditional approaches rely on decades of experience and spatial intuition. We believe the mathematics should do the heavy lifting so the cutter can focus on the craft.

Our volumetric engine converts 3D scans into signed distance fields — the same spatial representation used in medical imaging, 3D printing slicers, and physics simulation — then searches the full orientation space to find the mathematically optimal placement. The result is a precise cut plan with dop coordinates, alignment jig, and placement geometry ready for the bench.

gemjacket.com — Precision gem placement for hobbyists, professionals, and commercial operations.

Our Values
  • Accuracy over approximation — every placement is mathematically verified, not eyeballed
  • Browser-first — no installation, no desktop software, works on any device with a browser
  • Open formats — import and export using STL, the industry-standard 3D mesh format
  • Community-driven — share designs, vote on quality, build the library together
  • Transparent pricing — every tier is clearly defined, no hidden fees, cancel any time
Contact

Get in touch

Questions about pricing, enterprise licensing, volume discounts, or B2B integrations? We respond to all inquiries within one business day.

Email: hello@gemjacket.com

Support: support@gemjacket.com

For billing or subscription issues, include your username and the email address on your account.

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