B16 Mineral Identification

B16 Mineral ID Background Minerals are found in common materials like bricks, ceramics, and even toothpaste. Lots of minerals are used for jewelry, like diamonds, silver and corundum. Not every mineral makes good jewelry. Calcite and quartz are two common minerals, but which would make better jewelry? It depends on its properties. What properties do you think are important for good jewelry?

B16 Mineral ID Procedure A 1. An unknown mineral is either calcite or quartz. Examine Table 1 and discuss with your partner which properties will be most useful to identify the unknown mineral. Think about whether properties that are similar or different are most useful in identifying a material. 2. Select 5 useful properties to observe or test. 3. Review how to test these properties in Table 2.

B16 Table 1: Mineral Properties PROPERTY CALCITE QUARTZ COLOR Colorless, white, pink, blue, red, or green Colorless, white, pink, blue, purple, or yellow TRANSPARENCY Translucent Transparent LUSTER (SHINE/REFLECT) Dull Glassy HARDNESS (MOHS SCALE) 3 = soft 7 = hard STREAK COLOR White LIGHT REFRACTION Sometimes shows 2 images Always shows 1 image

B16 Table 2: Conducting Tests PROPERTY TEST COLOR Observe the color of the mineral TRANSPARENT Try to read letters through the mineral & see if it is transparent, translucent, or opaque. LUSTER Try to reflect light off of the mineral HARDNESS Try to scratch copper and glass with mineral STREAK COLOR Draw a line with the mineral on a white ceramic plate and observe the streak color LIGHT REFRACT Try to read a word through the mineral and observe if you see 1 or 2 images of the word.

B16 Mineral ID: Procedure B 4. Design an investigation to identify the mineral. When designing an investigation, think about: What is the purpose of your investigation? What 5 properties will you observe or test? Why did you choose these 5 properties? What materials do you need to do these tests? How will you record your data? How will the data help to name the mineral?

B16 Mineral ID: Procedure C 5. Write your experiment on separate paper. 6. Make a data table on that paper that has space for all data you need to record. You will fill it in during your experiment. 7. Get your teacher’s approval of your lab. 8. Conduct your lab and record your results. Decide which mineral it is: calcite or quartz. 9. Return all materials to your teacher. Clean up area. Turn in lab results with partner’s names.

B16 Mineral ID Lab Names of all lab partners:_________________ Calcite and Quartz identification PROPERTY NAME RESULT WITH DOT RESULT WITHOUT DOT Color Transmit Light Luster Hardness Streak Color Light Refract Mineral Identity Dot is … No Dot is …

B16 ID Analysis: Hr___ Date_________ Name___________________________ Answer with 1 paragraph each. Which properties did you test? Why those? Did everyone in class have the same data for each property? Why or why not? A. What is the dot material: calcite or quartz? B. Prove your decision with 4 pieces of evidence from your investigation. Compare your results to properties of both calcite and quartz. Would you buy calcite or quartz jewelry? Why?