November 1996 Gem Quiz

1. Jadeite (GIA) commonly can exhibit which of the following lusters?
   Silky
   Waxy
   Adamantine
   Dull

2. The Moh's hardness of cordierite can be?
   6.700
   6.600
   7.200
   7.700

3. Which of the following materials represents a Moh's hardness scale value of 8?
   Orthoclase
   Topaz
   Apatite
   Quartz

4. The polariscope may yield which of the following results when testing the Hex-trigonal gemstone tourmaline?
   Singly refractive or aggregate
   Aggregate
   Doubly refractive or aggregate
   Doubly refractive

5. Which of the red, transluscent gemstones listed below can exhibit the uneven fracture characteristics and resinous luster of the gemstone plastic?
   Beryl
   Oligoclase
   None of these
   Opal

6. Quartz is known to exhibit which of the following streak plate responses?
   Lemon yellow
   White
   Blue
   Reddish brown

7. Refractometer testing for the optic sign of the Orthorhombic gemstone iolite may yield which of the following results?
   Uniaxial negative
   Uniaxial positive
   Biaxial
   Uniaxial

8. The Moh's hardness of beryl can be?
   7.100
   8.200
   8.000
   7.300

9. Which of the following gemstones can be commonly found in the semi-transluscent form?
   Sodalite
   Conchiolin Coral
   All of them
   Rhodocrosite

10. Which of the following gemstones can exhibit the phenomena of iridescence?
    Diopside
    Glass
    Flourite
    Nephrite

11. Topaz is known to exhibit which of the following streak plate responses?
    Greenish yellow
    Iron black
    None of these
    Light gray

12. Which of the yellow, opaque gemstones listed below can exhibit the even fracture characteristics and resinous luster of the gemstone tortoise shell?
    Jadeite
    Amber
    None of these
    Opal

13. Synthetic Emerald Flux is known to exhibit which of the following responses to long wave ultra violet excitation?
    Red/pink
    Yellow
    Green
    There is no single best answer

14. Which of the black, opaque gemstones listed below can exhibit the even fracture characteristics and submetallic luster of the gemstone hematite?
    None of these
    Diopside
    Obsidian
    Corundum

15. Which of the following gemstones can be commonly found in the transluscent form?
    Conchiolin Coral
    Diopside
    Turquoise
    Rhodolite

16. Hydrogrossular is known to exhibit which of the following streak plate responses?
    Dark brown
    None of these
    Scarlet red
    Black

17. Conchiolin Coral is known to exhibit which of the following responses to long wave ultra violet excitation?
    Brown/tan
    Red/pink
    Green
    White

18. Spinel is found commonly in which of the following transparency classifications?
    All of these
    Transluscent
    Semi-transparent
    Opaque

19. Orthoclase can show which of the following responses when carefully tested with a dichroscope?
    Strong trichroic
    Moderate dichroic
    None of these
    Weak trichroic

20. Amber is known to exhibit which of the following responses to long wave ultra violet excitation?
    Brown/tan
    Red/pink
    Blue
    Orange

GemData will continue to have a future Gem Quiz each month. Would you like to see your questions used for a future Gem Quiz? GemData will be happy to post the persons name who submitted the question if so desired. Please submit your questions on any subject to do with the Gem, Diamond or Jewelry Industry with the answers to Lance Kanaby at lkanaby@buffnet.net