Gemology Certification Gem Treatments & Enhancements 2

Question 1

Which gemological instrument is most effective for detecting fracture-filling treatments in gemstones?

Accepted Answer

Microscope

Answer

A microscope reveals the diagnostic 'flash effect,' flow structures, and gas bubbles characteristic of fracture-filling materials.

Question 2

The 'flash effect'—an iridescent blue or orange flash visible under magnification—is most diagnostic of which treatment?

Accepted Answer

Fracture filling

Answer

The flash effect occurs because the filler material has a different refractive index than the host gem, creating interference colors at the filler-stone interface.

Question 3

Which of the following gemstones is NOT typically subjected to heat treatment as a standard trade practice?

Accepted Answer

Emerald

Answer

Emeralds are too fractured and thermally sensitive for heat treatment; they are instead treated with oils and resins.

Question 4

A diamond described as 'laser drilled' has undergone a treatment intended to improve which property?

Accepted Answer

Clarity

Answer

Laser drilling creates a microscopic channel to reach dark inclusions, which are then bleached or dissolved to improve the diamond's apparent clarity.

Question 5

Under GIA's grading system for colored stones, which disclosure term indicates no evidence of clarity or color treatment was found?

Accepted Answer

None detected

Answer

GIA uses 'None detected' to communicate that laboratory testing found no evidence of enhancement, while acknowledging detection limits.

Gemology Certification Practice Test

Gemology Certification Practice Test

Gemology Certification Gem Treatments & Enhancements 2