Carats: Gemstone Calculator

You bring care and a good eye to every stone. Thank you for using Carats for your work and collection. This update gives you more gemstone choices, detailed custom cut measurements and a separate, standalone Apple Watch app. CARATS ON APPLE WATCH - Convert carats, grams, points and milligrams at your wrist. - Use Gauge Sizes to compare inches, millimeters and gauge. - Open Gauge Guide for a thickness reference. - Browse gemstone specific gravity and cut factor charts. - Explore calculator graphs and share results. - Use all Watch tools without a usage limit or subscription. - Calculate without an iPhone companion or a saved history. MORE GEMSTONES AND SPECIES - Choose from 118 gemstone and material entries. - Find tanzanite, kunzite, hiddenite, iolite, amber and ametrine. - Select species including beryl, corundum, spodumene and zoisite. - Filter the picker by All, Gem varieties or Species. - Search names, species and specific gravity. - See species beside gemstone varieties. MORE CUT CHOICES - Try Asscher, baguette, princess and radiant cut options. - Compare brilliant cushion and step cushion variations. - Use reference cut factors for a standard weight estimate. - Open Advanced Gem when you want to describe the stone's proportions. - Choose single or double sided cabochons, including cushion shapes. A NEW ADVANCED GEM VIEW - Enter length and width in millimeters. - Measure height above the girdle, girdle thickness and depth below it. - Choose a faceted taper, dome, straight sides or a custom volume factor. - Set upper and lower profiles separately. - Add table and culet dimensions. - Describe a cushion outline with its corner radius. - Review total depth, outline area, estimated volume and carat weight. - See how the depth is divided above, at and below the girdle. MEASURE YOUR OWN CUSTOM CUT - Name an unusual cut and choose the outline that fits. - Enter a measured outline area for a unique shape. - Use a directly measured volume when you have one. - Add a custom gemstone or material name, species and density. - Keep notes on your measurement method. - Adjust taper fullness to describe the profile you are estimating. SAVE AND REVISIT ADVANCED GEMS - Save an Advanced Gem with Carats Pro. - Keep its cut, species, density, dimensions and custom measurements together. - Open a record to review those details and linked sale counts. - Reuse the measurements to start another estimate. - Edit the saved title or notes without replacing the original measurements. - Keep advanced gem details in JSON backups and calculation CSV exports. - Continue viewing, sharing and exporting existing records without Pro. THREE WAYS TO REVIEW YOUR GEMS - Regular Gems shows your saved standard estimates. - Advanced Gems shows detailed measurements and custom cuts. - Combined Gems brings both groups into an overview. - Compare gem counts, estimated carats, average weight and weight ranges. - Explore gemstone, species and cut charts. - Follow monthly gemstone activity and open the records behind an overview. CALCULATORS THAT ARE EASIER TO FIND - Browse calculator sections with familiar titles and descriptions. - Search for the tool you need. - Find Help, Share, Reset and Randomize in the top right menu. - Read usage help written for the calculator you have open. - Try an example with Randomize or restore starting values with Reset. - Open Advanced Gem from its link below the Gem Estimator. - Explore graphs to compare inputs and outputs. Carats Pro is required to save or edit calculations, add or edit sales, and import records on iPhone or iPad. Choose monthly or lifetime access. Gem weights remain estimates, so use a scale for actual weight.

This release is a full rebuild. The original Carats has been rewritten from scratch, and the result is faster, cleaner, and more capable than the version it replaces and while keeping the classic layout intact for anyone who doesn't want anything to change. Here's what's different. **MODERN GEM WEIGHT ESTIMATOR** The new Gem Weight Estimator (Modern) is a redesigned version of the original estimation tool built for how people actually use the app. The classic estimator is still here and unchanged and the new one runs alongside it. Key differences in the modern layout: - Live search field for the gemstone list and start typing "ruby" or "opal" and the list filters as you go, no more scrolling through 80+ entries to find what you need - Facet style shown in a horizontal scrollable row instead of a dropdown menu - Estimate, gemstone, and specific gravity always visible in the header card while you work - Same formula, same database, different interface and pick whichever one you prefer **FULL APP REDESIGN** - New home screen organizes all calculators into labeled sections: Carats, Gauges, Area, Distance, Volume, and Reference - Section icons and color accents make it easy to see at a glance what category you're in - Cards use a layered glass-style background that works well in both dark and light mode - Smooth gradient background throughout with subtle color glows keyed to each section's accent color - Navigation is faster and tap a calculator, get a result, go back, move to the next one **DARK MODE** Dark mode support has been built in from the ground up. Every screen, every card, every input field responds correctly to the system appearance setting. The dark background is a deep near-black with the section accent colors providing contrast without being hard on the eyes. **PERSISTENT INPUTS** Every input field in the app now saves its value automatically using on-device storage. This was added because it's genuinely annoying to re-enter a measurement you had a minute ago. Close the app mid-calculation and it's still there when you reopen it. Reset buttons are available on every screen when you want to start fresh. **GAUGE GUIDE** The gauge reference chart has been redesigned as a proper scrollable reference table. Gauge 1 through gauge 38 with decimal inch and millimeter equivalents, formatted for quick scanning. It's the kind of thing that used to live as a printed card on the workbench and now it's always in your pocket. **SHARE FROM ANYWHERE** Every calculator in the app now has a Share button. Tap it and a formatted summary of the current inputs and results goes out via the standard iOS share sheet and text, email, AirDrop, Notes, whatever you need. The gem weight estimator share includes the stone name, specific gravity, facet factor, all three measurements, and the estimated carat weight in a clean readable format. **RANDOMIZE** The Randomize button generates believable sample values across all three dimensions and picks a random gemstone and facet combination. It's useful for demonstrating the estimator to a customer or student, or for sanity-checking a formula result against a known stone type. **PERFORMANCE AND RELIABILITY** - All calculators are built on a shared model layer with consistent formatting, rounding, and locale-aware number handling - Number input parsing handles locale decimal separators correctly and comma vs. period depending on your region - Output rows show a clean "Out of range" label if a calculation produces an invalid result rather than crashing or showing garbage - Inputs are validated at the boundaries and negative values are clamped to zero, out-of-range gemstone or facet indices fall back safely **WHAT HASN'T CHANGED** The formula is the same. The gemstone database is the same. The classic layout is the same. If you were using the original app and it worked for you, it still works exactly the way it did. What is new is additive.