Name____________________ Period 1 2 3 4 5 6 7 8

Mineral Identification Lab

Color, Luster, Hardness, Streak

 

Purpose:

To identify minerals using 4 of the known methods of testing. These are Hardness,Color, luster, and Streak.

Materials:

Procedure:

In this lab you will use the 4 known mineral identification techniques that you have learned so far. These include color, luster, hardness, and streak.

1. Each group will have a set of minerals to test. These sets of minerals are for that group only. DO NOT MIX AND MATCH! Mixing the minerals from table to table will cause data to be incorrect, and therefore result in poor lab results, and possibly failure on the lab.
 
2. Each member of the group will test each mineral for color, luster, hardness, and streak. You have all previously used each of these lab techniques, and now it is time to put them all to use in this lab. All data will be recorded on the lab data sheets provided in class or on-line.
 
3. HINTS....HINTS....HINTS....HINTS....HINTS....HINTS...HINTS...I hope you all get the hints....
Luster : Remember that you will need to look for the way a mineral reflects light. You also have in you're possession the notes on luster, and some of the terms used to describe a minerals luster. Use them + you're own descriptions.
Color: Remember that color is how a mineral looks to YOU. Be descriptive and make sure to mention all colors that you observe.
Hardness: This test will require you're great abilities to eliminate choices. Make sure you use MOH'S hardness scale, and the Field Scale that you have in you're notebooks. YOU WILL NEED BOTH. Start with the fingernail test to see if the mineral is harder or softer than 2. If it is easy to scratch with the fingernail, then you can safely assume that the mineral is as hard or softer than 2. If it will not scratch with the fingernail then you have to assume that it is harder than 2. This will require you to test further. Only test until you have found the approximate hardness. Anything harder than 6.5 just put 6.5+. Anything softer than 2 , use (1-2). Another hint when using the steel file. Don't saw away at the rock. One scratch like I showed you in class is all you need to do to get results.
Streak: Remember to use the streak plates carefully. Apply only slight pressure to the mineral, and only run it across the plate once. Repeated use back and forth will give a positive test in a lot of cases. This taints the data when the mineral sample will usually not streak when done properly.
LAST HINT: Make sure that you are descriptive. Make sure that you ANSWER the conclusion questions thoroughly and completely. Make sure that you proof your work, and get it done ON TIME!!!!!!!!!!!
4. After you have recorded all data, go back through your lab data and check it with the data from the rest of your group. Start answering the conclusion questions in rough draft form first. Rough drafts will be required with this lab. Failure to do a rough draft will reduce your lab grade one full grade.