CDG CDG Diamond Treatments & Enhancements 2

Question 1

What does HPHT stand for in the context of diamond treatment?

Accepted Answer

High Pressure High Temperature

Answer

HPHT stands for High Pressure High Temperature, a treatment that mimics natural diamond formation conditions to alter color.

Question 2

HPHT treatment is primarily used to accomplish which of the following?

Accepted Answer

Improve or change the color of diamonds

Answer

HPHT treatment is primarily used to improve or change diamond color, often converting brown or near-colorless stones to colorless or fancy colored.

Question 3

Which spectroscopic method is most reliable for detecting HPHT treatment in diamonds?

Accepted Answer

Infrared (FTIR) and UV-Vis spectroscopy

Answer

FTIR and UV-Vis spectroscopy reveal characteristic absorption patterns in HPHT-treated diamonds not present in untreated stones.

Question 4

Irradiation treatment of diamonds most commonly produces which colors?

Accepted Answer

Blue, green, or fancy yellow

Answer

Irradiation creates or modifies color centers within the crystal lattice, typically producing blue, green, or fancy yellow colors.

Question 5

What is the primary consumer safety concern with certain irradiation treatment methods?

Accepted Answer

Residual radioactivity in some treatment methods

Answer

Some irradiation methods can leave residual radioactivity in diamonds, requiring monitoring and clearance before sale to consumers.

(CDG) Certified Diamond Grader Practice Test