Test your knowledge of refractometer gem analysis with this mini-quiz. You can review material on any question you miss at the end of the quiz.
Parallax is caused by:
A. Double refraction
B. A facet not being flat
C. Lenses that need cleaning
D. All the above
E. None of the above
If you use a red filter with your refractometer, you need to make an adjustment to your reading of
A. – 0.005
B. + 0.589
C. Neither
D. Both
If you’re testing a gem and measured a high RI of 1.612 and a low RI of 1.608, the stone’s birefringence is 0.004.
A. True
B. False
A moderate-sized spinel inclusion in a spinel host gem will have a significant effect on its value.
A. True
B. False
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Parallax is caused by:
A. Double refraction
B. A facet not being flat
C. Lenses that need cleaning
D. All the above
E. None of the above
If you use a red filter with your refractometer, you need to make an adjustment to your reading of
A. – 0.005
B. + 0.589
C. Neither
D. Both
If you’re testing a gem and measured a high RI of 1.612 and a low RI of 1.608, the stone’s birefringence is 0.004.
A. True
B. False
A moderate-sized spinel inclusion in a spinel host gem will have a significant effect on its value.
A. True
B. False
Test your knowledge of refractometer gem analysis with this mini-quiz. You can review material on any question you miss at the end of the quiz.
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