Stone Keeper

Build a private, visual catalog of the rocks, minerals, crystals, fossils, and other geological finds you collect. Photo comparison in version 1.0 covers five types only: calcite, chalcopyrite, fluorite, granite, and marble. This experimental feature makes a best-effort comparison and may be wrong, return no identification, or show several possible alternatives. Suggestions have low evidence and are never a definitive identification. You can always save a find as unidentified. Other rocks, minerals, and fossils can be collected, but are not covered by this photo comparison. Stone Keeper helps you: • add one to three photos of a find • record the date, a broad place label, notes, and simple observations • organize finds in a visual cabinet and timeline • search, favorite, edit, and record where the physical specimen is stored • compare photos on device with bundled reference specimens when available • save a find as unidentified whenever no responsible candidate can be suggested • keep app suggestions, your confirmations, and expert-checked entries clearly separate • review cautious safety guidance and useful next steps Your saved collection stays on your device. The collection and photo comparison work offline, without Apple Intelligence, an account, or an external API. No API key is needed. Stone Keeper includes no ads, tracking or analytics SDKs. Important: Photo-based results are possible visual matches, not laboratory identification, valuation, or safety clearance. The app does not determine exact composition, origin, age, authenticity, radioactivity, asbestos content, or whether a specimen is safe. If a find may be hazardous or important, contact a qualified professional.