Observed arrival · 2026-11-01

Pleochroma: a gemstone faceting studio with spectral optics

pleochroma.com Visit website

Editorial interest 83/100 Selection signal · not a rating of the site

Pleochroma is free, open-source software for designing gemstone cuts and rendering how light behaves inside them, with desktop and browser versions described on the site.

Landing page captured for the 2026-11-01 issue.

For: Gem cutters and gemstone faceting designers
Worth noticing: Its rough planner compares the best ten layouts while mixing up to 99 designs against a block, pebble, or scanned rough.

Field notes

The listed workflow spans importing GemCAD-style .asc files, editing cutting instructions, and previewing a cut with material-specific optical effects. The homepage says the optional GPU kernel is checked against a CPU reference; browser GPU rendering is limited to isotropic stones in Chrome and Edge. Android access is described as build-from-source rather than an app-store download.

Observed signals

Read the marks

Editorial observations of this landing page, not a rating.

○OpenPublic substance visible

⊠LoginAccess appeared gated

✦PrettyNotable craft visible

●ProPolished or operationally mature

◎NicheUnusually specific use

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