CS 21

Question 1

1. Almost all tanzanite is
   A. untreated.
   B. irradiated.
   C. heat treated.
   D. clarity enhanced.

Answer 1

heat treated

Question 2

1. Which of the following gems is the most economically important?
   A. Iolite
   B. Tanzanite
   C. Andalusite
   D. Chiastolite

Answer 2

Tanzanite

Question 3

1. Where was tanzanite discovered?
   A. Tunduru
   B. Mangari
   C. Merelani
   D. Umba River Valley

Answer 3

Merelani

Question 4

1. Which of the following is a major source of cat’s-eye chrysoberyl?
   A. Vietnam
   B. Colombia
   C. Sri Lanka
   D. Cambodia

Answer 4

Sri Lanka

Question 5

1. Untreated tanzanite is typically
   A. violet.
   B. bluish.
   C. purple.
   D. brownish.

Answer 5

brownish

Question 6

1. Iolite is
   A. untreated.
   B. irradiated.
   C. heat treated.
   D. diffusion treated.

Answer 6

untreated

Question 7

1. Tanavyte is a trade name for
   A. purple glass.
   B. synthetic zoisite.
   C. synthetic forsterite.
   D. purple synthetic YAG.

Answer 7

purple synthetic YAG

Question 8

1. Alexandrite was discovered in
   A. 1830.
   B. 1897.
   C. 1955.
   D. 1967.

Answer 8

1830

Question 9

1. The color change in alexandrite is caused by
   A. iron.
   B. cobalt.
   C. chromium.
   D. magnesium.

Answer 9

Chromium. Chrysoberyl consists mostly of beryllium aluminum oxide, but traces of chromium create the magic touch that causes alexandrite’s color change

Question 10

1. In iolite, the most valuable main face-up color is
   A. blue.
   B. gray.
   C. violet.
   D. yellow.

Answer 10

blue

Question 11

1. What color is top-quality alexandrite in daylight?
   A. Red
   B. Yellow
   C. Bluish green
   D. Yellowish green

Answer 11

blueish green

Question 12

1. The name tanzanite was given to transparent blue zoisite by
   A. Tiffany & Co.
   B. Manuel D’Souza.
   C. a Masai tribesman.
   D. the Tanzanian government.

Answer 12

Tiffany & Co

Question 13

1. Tanzanite’s most prized color is
   A. dark purple or violet.
   B. light purple or violet.
   C. pure blue or intense violet-blue.
   D. strongly saturated purple or violet.

Answer 13

pure blue or intense violet-blue

Question 14

1. What changes during alexandrite’s color-change effect?
   A. Hue
   B. Tone
   C. Saturation
   D. Tone and saturation

Answer 14

hue

Question 15

1. The most prized chatoyant gem is
   A. tiger’s-eye quartz.
   B. hawk’s-eye quartz.
   C. cat’s-eye tourmaline.
   D. cat’s-eye chrysoberyl.

Answer 15

cat’s-eye chrysoberyl