1. What is the range of wavelengths for visible light in the electromagnetic spectrum?

2. What is the primary reason for the color observed in gemstones?

3. Which element is responsible for the red color in rubies?

4. Which type of gem minerals gets their color from impurities or trace elements?

5. What optical phenomenon is responsible for the "fire" in diamonds?

6. Selective absorption in gemstones primarily depends on which of the following?

7. What does the visible spectrum analysis of a gemstone help to identify?

8. Which component of a spectroscope is responsible for dispersing light into its component colors?

9. Pleochroism in gemstones refers to which property?

10. A dichroscope is used to detect which property in gemstones?

11. What is the primary use of color filters in gemology?

12. What does a Chelsea color filter help to identify?

13. Which process is NOT involved in causing color in gemstones?

14. Which element often causes the green color in emeralds?

15. Which of the following is an example of an idiochromatic gemstone?

16. Which gemstone is known for showing diffraction and a play of color effect?

17. What determines the specific wavelengths of light absorbed by a gemstone?

18. Which gemstone typically shows sharp absorption lines in the green and blue regions of the spectrum?

19. What does a typical spectroscope result indicate in gemology?

20. Tanzanite exhibits which type of pleochroism?