What are your learning objectives for mineral identification?

[Scott Brande]

My student kits of minerals are filled with "student-grade" material. A lump of sulfur, no visible crystals, for example. So students ID sulfur on the basis of only streak and odor. OK. Good enough. 

How far should an intro ID lab go with sample quality? Seems to depend on the instructor's learning objectives for the activity.

LOs could be quite different. What are the cognitive tasks that guide instruction?

1) e.g., learn to ID by the one or two outstanding properties (sulfur is yellow and stinks); magnetite attracts a paperclip, etc.

2) e.g., you really need to distinguish K-spar from plagioclase by recognizing cleavage and exsolution lamellae

3) e.g., what's more important is that you practice and develop cognitive skills for observing and recognizing features, and using an ID table to complete an identification

Why ID minerals at all if you don't assess students? So assessments must be based on LOs. What are the cognitive tasks selected for assessment?

1) You'll get some unknown minerals on the quiz, and you need to ID them and write their names [and maybe some formulas]

2) you'll get some unknown minerals on the quiz, and you need to recognize and describe features needed for identification

3) you'll get some unknown minerals on the quiz, and you need to use a reference table to ID the sample.

Difficult choices need to be made that determine the purposes for mineral identification. These may vary greatly from one instructor to another.

What's yours?