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To enter the 2002 Challenge, you must mark your answers on the response card provided in the Spring 2002 issue. Entries are due no later than August 5, 2002. All entries will be acknowledged with a letter and an answer key after the due date; the correct answers also will be posted on this Web page.
Score 75% or better, and you will receive a GIA Continuing Education Certificate. If you are a member of the GIA Alumni Association, you will earn five Carat Points toward GIA's Alumni Circle of Achievement. Earn a perfect score, and your name will also be featured in the Fall 2001 issue of Gems & Gemology.
The following 25 questions are based on information from the four 2001 issues of Gems & Gemology.
1. The most common method of producing or enhancing color in South Sea “golden” cultured pearls involves
A. irradiation.
B. high pressure and high temperature.
C. a chemical or organic dye.
D. bleaching.
2. Australia’s Argyle diamond mine is a major source for
A. exceptionally large diamonds.
B. brown and pink diamonds.
C. vivid blue diamonds.
D. well-formed cubic rough that is easily polished.
3. Considering fire and brilliance together for round-brilliant cut diamonds, cutters should remember:
A. There are many sets of proportions that will yield average to above average results for both.
B. It is possible to determine a single set of proportions that will deliver maximum performance in a single round brilliant.
C. Smaller table size increases results for both.
D. Facet size was found to have little effect.
4. Ammolite is
A. a mineral with the composition CaCO3 that is found in metamorphic rocks.
B. a trade name for the iridescent nacreous layer of certain fossil ammonites.
C. being formed today in mollusks found in the Pacific and Indian Oceans.
D. identical in all respects to the iridescent shell material called lumachelle.
5. The bright orange color of gem spessartine from Ramona (San Diego County, California) is achievable only with low ______ contents.
A. Fe
B. Mn
C. Ca
D. Al
6. Which of the following was [were] found to have a significant effect on the amount of fire produced by a round brilliant diamond?
A. Culet size
B. Girdle thickness
C. Lower-girdle facet length
D. Both A and B, taken together
7. One historical source of inspiration for the works of North American gem cutters has been the ________ era, in which gem carvings and glass were included in pieces of fine jewelry.
A. Edwardian
B. Art Nouveau
C. Art Deco
D. Victorian
8. The best explanation for the iridescence of Ammolite is
A. interference.
B. diffraction.
C. the incorporation of chromophores during formation.
D. diffusion treatment of the rough material after it has been mined.
9. Indications that the asterism in a polished gem has been artificially created might include
A. an unusual number of rays in the star.
B. an unnatural appearance of the rays in the star.
C. a gem variety that rarely displays asterism.
D. all of the above.
10. Argyle diamonds are found in
A. eclogitic kimberlite.
B. peridotitic kimberlite.
C. olivine lamproite.
D. lamprophyre.
11. The greatest production of gem-quality “Paraíba” tourmaline from the São José de Batalha mine occurred in
A. 1982–1983.
B. 1990–1991.
C. 1998–1999.
D. 2000.
12. The most diagnostic chemical elements for identifying synthetic red beryl are
A. V and Cr.
B. Cu and Zn.
C. Mn and Fe.
D. Co and Ni.
13. The vast majority of diamonds from Australia’s Argyle mine are polished in
A. Antwerp.
B. Israel.
C. India.
D. Thailand.
14. Fire in a round brilliant diamond is
A. the same as dispersion.
B. the result of dispersion.
C. the amount of light emanating from the crown.
D. the result of diffusion.
15. Although there is no universally accepted definition, the term malaya is generally used for garnets that are pink to pinkish orange, composed primarily of
A. spessartine-almandine.
B. intermediate pyrope-almandine.
C. intermediate pyrope-spessartine.
D. low-Fe, low-Cr pyrope.
16. A characteristic feature of hydrothermal synthetic red beryl is the presence of _______-related absorption bands between 4200 and 3200 cm-1.
A. iron
B. titanium
C. cobalt
D. water
17. As used in the article, “Paraíba” tourmaline is a trade term that
A. may not be applied to a cuprian tourmaline with more than 2 wt.% CuO.
B. may be applied to any tourmaline, regardless of geographic origin, that contains 0.1–2.0 wt.% CuO.
C. may only be applied to a tourmaline that contains at least 0.1 wt.% CuO and comes from Brazil’s Paraíba State.
D. applies to any elbaite from Brazil’s Paraíba State regardless of color and CuO content.
18. Since the late 1990s, spessartine production from Ramona, California, has been overshadowed by fine material from
A. Madagascar and Tanzania.
B. Namibia and Nigeria.
C. Colombia and Canada.
D. Afghanistan and Pakistan.
19. Ammolite currently is fashioned primarily into
A. stabilized solids.
B. free-form naturals.
C. assembled stones (triplets).
D. assembled stones (doublets).
20. To achieve the best luster and color, Chinese pearl culturers typically
A. culture mussels that are at least 5 years old.
B. insert pieces of tissue into the posterior mantle lobe of the H. cumingi mussel.
C. insert pieces of mantle tissue from the Akoya oyster.
D. use beads fashioned from wax.
21. Spessartine from Ramona, California
A. is characterized by abundant inclusions of fine apatite crystals.
B. may have linear clouds and inclusions of albite and columbite.
C. has R.I. and S.G. values that distinguish it from other pegmatite gem spessartines worldwide.
D. is impossible to distinguish from Mexican fire opal of the same color.
22. Since the early 1980s, deposits of the relatively rare gem mineral jeremejevite have been reported in each of the following localities except
A. Namibia.
B. the Eifel region of Germany.
C. Madagascar.
D. Tajikistan.
23. The following characteristic(s) are indicative of natural yellow color in South Sea cultured pearls from Pinctada maxima:
A. absorption in the UV region between 330 and 385 nm.
B. brown fluorescence to long-wave UV radiation.
C. very light blue fluorescence to long-wave UV radiation.
D. both A and B.
24. Inclusions of _______ provide unequivocal evidence that a pale purplish pink pyrope is from Italy’s Dora Maira Massif
A. ellenbergerite
B. dolomite
C. wollastonite
D. tinaksite
25. For more than 70 years, _______ has formed the backbone of pearl identification.
A. Raman spectrometry
B. infrared spectroscopy
C. proton-induced X-ray emission [PIXE] analysis
D. X-radiography
Remember, to enter the 2002 Challenge you must mark your answers on the response card provided in the Spring 2002 issue
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