Earth Science 11 Name ________________________ Mineral I.D. Lab Purpose: __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ Procedure: 1. Color. Mentally take the gray out of the mineral and describe it as best you can. Remember that one mineral can have many colors, and many minerals can have the same color. Some minerals tarnish. 2. Hardness. Ranges from 1 – 10 on Mohs’ Scale. A mineral is harder than anything it can scratch; it is softer than anything it can’t scratch. Using your fingernail, a copper penny, a steel nail, a piece of glass, and a sample of quartz, you should be able to determine the hardness of any material quite accurately. It is important to be accurate with this test – if the hardness of a mineral sample is 5, you should get a result between 4 and 6. 3. Streak. Color of powder on a streak plate. This is more consistent from sample to sample that color is. Metallic minerals have a dark streak, non-metallic minerals have a light streak. 4. Luster. How does the mineral reflect light? Is it metallic or non-metallic? If non-metallic, is it vitreous (glassy), dull (earthy), waxy or pearly? Observations: Discussion Questions: 1. Which property did you find: a) Most useful, why? b) Least Useful, why? 2. Which mineral was magnetic? 3. Which mineral was: a) Hardest? b) Softest? 4. Which mineral looked like gold? 5. What does the term vitreous mean?