In this test, 4 mineral grains are shown and 7 questions are going to be raised. When pressing on the crystal, its interference figure will appear.

Question 1: optic group

Question 2: optic sign

Question 3: 2V angle

Question 4: orientaction of the crystal 1 cut

Question 5: orientaction of the crystal 2 cut

Question 6: orientaction of the crystal 3 cut

Question 7: orientaction of the crystal 4 cut

After every answer, you may go to back to this page to ask for a new question.