The mineral zircon (zrsi04) typically contains several hundred to several thousand ppm u but much lower concentrations of th. explain why both statements are true. 4. explain why quartz is typically > 99.9% pure sio2 while other minerals contain significant concentrations of elements not in their formulas. 5. explain why the color of many minerals can vary widely, but other properties, e. g., cleavage (or lack thereof) and hardness are much more consistent. 6. a mineral contains 63.5% fe and 36.5% s. derive the chemical formula for the mineral, using integer amounts of fe and s. show your work.