Science, Tech, Math › Science 10 Colored Crystal Recipes Grown Naturally Share Flipboard Email Print Science Chemistry Projects & Experiments Basics Chemical Laws Molecules Periodic Table Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated July 23, 2018 This is a list of colored crystal projects. These crystal colors are natural, not caused by food coloring or another additive. You can grow natural crystals in pretty much any color of the rainbow! 01 of 10 Purple - Chromium Alum Crystals Ra'ike/Wikimedia Commons/CC BY-SA 3.0 These crystals are deep violet if you use pure chromium alum. If you mix the chromium alum with regular alum, you can get lavender crystals. This is a stunning type of crystal that is easy to grow. 02 of 10 Blue - Copper Sulfate Crystals Crystal Titan/Wikimedia Commons/CC BY-SA 4.0 Many people find this to be the most beautifully colored crystal you can grow yourself. This crystal is also easy to grow. You can order this chemical or you may be able to find it sold as an algicide for use in pools, fountains, or aquaria. 03 of 10 Blue-Green - Copper Acetate Monohydrate Crystals Wikimedia Commons/Public Domain This recipe produces lovely blue-green monoclinic crystals. 04 of 10 Golden Yellow - Rock Candy Norbert Eisele-Hein / Getty Images Sugar crystals grown using white sugar are clear, though they can be made any color using food coloring. If you use raw sugar or brown sugar, your rock candy will be naturally gold or brown. 05 of 10 Orange - Potassium Dichromate Crystals Potassium dichromate is also known as the mineral lopezite. A13ean/Wikimedia Commons/CC BY-SA 3.0 Potassium dichromate crystals will be bright orange rectangular prisms. It's an unusual color for crystals, so be sure to give it a try. 06 of 10 Clear - Alum Crystals Ude/Wikimedia Commons/CC BY-SA 3.0 These crystals are clear. Though they do not have bright colors, they can be grown quite large and in a wonderful array of shapes. 07 of 10 Silver - Silver Crystals Alchemist-hp/Wikimedia Commons/CC BY-SA 3.0 de Silver crystals are a common crystal to grow for observation under a microscope, though they can be grown larger, too. 08 of 10 White - Baking Soda Stalactites wikiHow These white baking soda or sodium bicarbonate crystals are intended to simulate stalactite formation in a cave. 09 of 10 Glowing - Fluorescent Alum Crystals These easy-to-grow alum crystals glow, thanks to the addition of a little fluorescent dye to the crystal growing solution. Anne Helmenstine Making crystals that glow when exposed to black light is as easy as making non-glowing crystals. The color of the glow you get depends on the dye that you add to the crystal solution. 10 of 10 Black - Borax Crystals Anne Helmenstine You can make crystals that are translucent or solid black by adding black food coloring to ordinary clear borax crystals.