Gem Weight Estimator for Windows A simple, easy to use gem weight estimator app for Windows 8.1 If you are looking for a way to simply and easily calculate weight estimations for gemstones, Gem Weight Estimator is the app for you. The main screen is clean and uncluttered making it easy to select the gemstone and shape and enter the measurements to quickly calcuate the estimated weight. Featues: Extensive list of gemstones and shapes to pick from Uses numeric keypad for quick entry of measurements