GIA Diamond Grading and Identification 5

Question 1

Which type of diamond treatment involves filling surface-reaching fractures with a glass-like substance to improve apparent clarity?

Accepted Answer

Fracture filling

Answer

Fracture filling uses a glass-like resin to fill surface-reaching fractures, improving the diamond's apparent clarity.

Question 2

What does 'laser drilling' accomplish when used to treat a diamond?

Accepted Answer

It creates a channel to a dark inclusion so bleaching or acid can lighten it

Answer

Laser drilling bores a tiny channel to a dark inclusion, allowing bleaching agents or acid to lighten or remove the inclusion.

Question 3

On the GIA scale, which clarity grade is just below 'Internally Flawless (IF)'?

Accepted Answer

VVS1

Answer

VVS1 (Very Very Slightly Included 1) is the grade immediately below Internally Flawless on the GIA clarity scale.

Question 4

Which phenomenon causes some diamonds to appear a different color face-up than when viewed from the side?

Accepted Answer

Color zoning

Answer

Color zoning is the uneven distribution of color within a diamond, causing different color appearances depending on viewing angle.

Question 5

What is the hardness of diamond on the Mohs scale?

Accepted Answer

10

Answer

Diamond is the hardest natural material, rating 10 on the Mohs scale of mineral hardness.

(GIA) Certified Diamonds Gemological Institute of America Practice Test