Jewelry Design Gemstones and Precious Stones 1 — Questions and Answers
Question 1: Which gemstone hardness scale is universally used in jewelry to rate scratch resistance?
- Vickers Scale
- Rockwell Scale
- Mohs Scale (Correct answer)
- Brinell Scale
Correct answer: Mohs Scale
The Mohs Scale rates mineral hardness from 1 (talc) to 10 (diamond) and is the standard reference in gemology and jewelry.
Question 2: What is the term for the weight unit used to measure gemstones?
- Gram
- Grain
- Carat (Correct answer)
- Ounce
Correct answer: Carat
A carat equals 0.2 grams and is the standard unit for measuring the weight of gemstones in the jewelry industry.
Question 3: Which of the following is NOT a variety of corundum?
- Ruby
- Sapphire
- Emerald (Correct answer)
- Padparadscha
Correct answer: Emerald
Emerald is a variety of beryl, while ruby, sapphire, and padparadscha are all varieties of the mineral corundum.
Question 4: What optical phenomenon causes a star-shaped light pattern in certain gems like star sapphires?
- Asterism (Correct answer)
- Chatoyancy
- Adularescence
- Labradorescence
Correct answer: Asterism
Asterism is the optical effect caused by needle-like inclusions that reflect light into a star pattern, seen in star sapphires and star rubies.
Question 5: Which treatment is most commonly applied to emeralds to improve their clarity?
- Heat treatment
- Irradiation
- Oil or resin filling (Correct answer)
- Fracture sealing with glass
Correct answer: Oil or resin filling
Emeralds are routinely filled with cedar oil or synthetic resin to reduce the visibility of surface-reaching fractures, a widely accepted trade practice.
Question 6: What is the name for the category of gemstones that includes diamonds, rubies, sapphires, and emeralds?
- Semi-precious stones
- Precious stones (Correct answer)
- Ornamental stones
- Mineral gems
Correct answer: Precious stones
Diamonds, rubies, sapphires, and emeralds are traditionally classified as precious stones, while all other gemstones are often called semi-precious.
Jewelry Design Gemstones and Precious Stones 1
Which gemstone hardness scale is universally used in jewelry to rate scratch resistance?