# Birefringence — Michel-Lévy Color Chart > Interactive Michel-Lévy color chart for mineral identification via birefringence calculation. (iPhone/iPad app by Andrew Barlow.) - Source: https://appshunter.io/ios/app/birefringence/id1354688131 (this page in markdown: same URL + `.md`) - Developer: [Andrew Barlow](https://appshunter.io/developer/1229786938) - Category: Utilities, Education - Price: $2.99 - Rating: 4.80/5 from 9 App Store ratings · 9 written reviews indexed - Age rating: 4+ - Requires: iOS 12.0 · 14 MB - Languages: American English - Released: 2018-03-22 - Data updated: 2026-08-24 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/birefringence/id1354688131/reviews.md ## What is Birefringence? An interactive Michel-Lévy interference color chart that features a database of 562 minerals. Click on your observed color and section thickness, and the birefringence of your section will be automatically calculated, and candidate minerals will be suggested. The range of the chart can be be set to between 200 nm and 2500 nm. The chart can be offset by + or - λ, + or - λ/4. The chart can be used as a traditional nomogram, or displayed in a "simple" mode without the clutter of radial lines (which are no longer necessary on an interactive chart). Based on the methods of Sørensen (2013), the colors in the chart are a much truer representation of the colors seen at the microscope eye pieces than existing printed nomograms. The app includes optical and physical characteristics of candidate minerals including birefringence (minimum, maximum and mean), relief, optical character, pleochroism, color and cleavage. The app includes the Raith-Sørensen color chart, which is also interactive. The Raith-Sørensen chart is a direct representation of interference color as a function of birefringence and sample thickness (Sørensen 2013). A useful utility for polarized light microscopy, polariscopy, optical mineralogy, stress optics, or anyone with an interest in birefringent materials. ## Key features - Interactive Michel-Lévy color chart - Database of 562 minerals - Automatic birefringence calculation - Adjustable chart range (200-2500 nm) - Simple display mode - Includes optical and physical mineral characteristics ## Recent user reviews (9 of 9) All indexed reviews: https://appshunter.io/ios/app/birefringence/id1354688131/reviews.md ### 3/5 — Update *2026-07-05* Please add asbestos to the mineral list in an update. ### 4/5 — A little gem *2025-03-22, version 1.20* Hobby microscopist enjoying this little app. Runs well on my MacBook too which is a bonus. That the app shows ±λ-plate colours is a very nice feature. Would be lovely if it also simultaneously displayed ±1/4λ-plate colour swatches too! ### 5/5 — Another great App from this developer *2022-03-01, version 1.20* Updated review : 01-March-2022 Thank You … ‘great’ just got even better !! . Beautifully executed, and very useful. Spoiled slightly by the advertisements ... Please consider charging a modest fee for an Ad-free experience. ### 5/5 — A better Michel-Levy chart *2021-12-27* Birefringence adds value to the classic Michel-Levy interference color chart by leveraging the intuitive interface of yor mobile device. Scientifically sound and thoroughly documented. An outstanding tool for optical petrography research and education! ### 5/5 — ***ABSOLUTELY AMAZING!*** *2021-01-06* It literally saved me! Thank you for creating such an amazing handy app. I introduced it to many of my friends and classmates and even some of my professors and they were absolutely blown away by its simplicity...I’m just kinda sad about how underrated it is. Well done! **Developer response:** Thanks so much for the review! It’s really appreciated! Andy ### 5/5 — Geology student *2020-10-30* This is an incredibly helpful app **Developer response:** Thanks so much for the review! ### 5/5 — So dope!! *2019-10-26* Great job with this app. **Developer response:** Thanks! I really appreciate the review. ### 5/5 — Great for quick Petrography reference! *2019-01-10* Very useful quick reference. I appreciate the interactive nature of the charts, and the “compensator” function. **Developer response:** Thanks so much for the review! ### 5/5 — Great idea! *2018-09-26, version 1.05* Really great app! ## Frequently asked questions about Birefringence ### What is Birefringence used for? Birefringence is an interactive Michel-Lévy color chart designed for mineral identification. It calculates birefringence based on observed color and section thickness, suggesting candidate minerals from its database of 562 minerals. ### How accurate are the colors in Birefringence? The colors in Birefringence are stated to be a much truer representation of colors seen through microscope eyepieces than traditional printed nomograms, based on the methods of Sørensen (2013). ### What information does Birefringence provide about minerals? Beyond birefringence, Birefringence includes optical and physical characteristics of candidate minerals such as relief, optical character, pleochroism, color, and cleavage. ### What is the price of Birefringence? Birefringence is a paid application, priced at $2.99. ### On which devices can I use Birefringence? Birefringence is supported on iPhone, iPad, and iPod devices. ### How often is Birefringence updated? The latest version of Birefringence is 1.20, and it was last updated on February 27, 2022. ### Does Birefringence have ads? No, Birefringence does not contain advertisements. ### What age rating does Birefringence have? Birefringence has an age rating of 4+, making it suitable for a wide range of users. ## Version history (last 5 releases) ### 1.20 — 2022-02-27 All adds have been removed. ### 1.10 — 2021-01-27 Icons have been added to the button. General app maintenance and updates. Less intrusive Ad layout. ### 1.09 — 2019-04-10 The Raith–Sørensen chart has been made much more interactive. A panel in the chart view now shows the observed color, as well as the colors plus and minus λ. ### 1.08 — 2019-03-01 The layout of the mineral table has been improved. ### 1.07 — 2018-10-17 Improved the share function ## Apps similar to Birefringence | App | Rating | Price | Category | | --- | --- | --- | --- | | [FossilVault: Specimen Vault](https://appshunter.io/ios/app/fossilvault-specimen-vault/id6748266414) | 5.0 (5) | Free | Utilities | | [Plusly Calculator](https://appshunter.io/ios/app/plusly-calculator/id1576071621) | 5.0 (1) | Free | Utilities | | [StraboField](https://appshunter.io/ios/app/strabofield/id1555903455) | 4.5 (19) | Free | Utilities | | [Recollector App HD](https://appshunter.io/ios/app/recollector-app-hd/id665249872) | 4.8 (4) | Free | Utilities | | [LisenOut](https://appshunter.io/ios/app/lisenout/id6475392352) | — | Free | Utilities | | [Nite Time - 2](https://appshunter.io/ios/app/nite-time-2/id6746581094) | — | Free | Utilities | ## More apps by Andrew Barlow - [Microscope Resolution](https://appshunter.io/ios/app/microscope-resolution/id1229786939) - [Koehler Tutor](https://appshunter.io/ios/app/koehler-tutor/id1281328178) All apps by Andrew Barlow: https://appshunter.io/developer/1229786938 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-24.*