By Anne Marie Helmenstine, Ph.D., About.com Guide
Calcite crystals are calcium carbonate (CaCO3). They are generally white or clear and can be scratched with a knife.
Big Alum CrystalSugar Crystals or Rock CandyBorax Snowflake
Chemical ElementsGemstone Photo GalleryLab Glassware Photo Gallery
©2009 About.com, a part of The New York Times Company.
All rights reserved.