DCA Diamond Treatments & Enhancements 3

Question 1

According to FTC guidelines, how must a treated diamond be described in retail advertising?

Accepted Answer

The treatment must be clearly and conspicuously disclosed

Answer

No special description is required if the treatment is minor

Answer

Only GIA-certified treated diamonds require disclosure

Answer

Disclosure is only required if the customer specifically asks

Question 2

Which of the following correctly describes the effect of HPHT treatment on a diamond's crystal structure?

Accepted Answer

It rearranges nitrogen aggregates to reduce brown coloration

Answer

It adds a coating that masks color

Answer

It drills channels to remove inclusions

Answer

It fills existing fractures with a high-refractive-index material

Question 3

How do treated diamonds generally compare to untreated diamonds of similar apparent quality in terms of resale or trade-in value?

Accepted Answer

Treated diamonds typically sell for less than untreated stones of similar apparent grade

Answer

Treated diamonds command a significant premium due to improved appearance

Answer

Treated and untreated diamonds have identical market values

Answer

Only irradiated fancy colored diamonds lose value; other treatments have no impact

Question 4

What notation does a GIA grading report use to indicate that a diamond has undergone fracture filling?

Accepted Answer

GIA does not grade fracture-filled diamonds and returns them without a report

Answer

The report is marked 'Clarity Enhanced' in red

Answer

A 'clarity treatment' note appears with a disclosure that the report is based on the treated state

Answer

The diamond receives a separate clarity grade for treated and untreated condition

Question 5

Which safe cleaning method is recommended for fracture-filled diamonds to avoid damaging the treatment?

Accepted Answer

Warm water with mild soap and a soft brush

Answer

Ultrasonic cleaner with ammonia solution

Answer

Steam cleaner at high pressure

Answer

Boiling water immersion

Question 6

What is the most reliable instrument a gemologist uses to detect HPHT treatment in a colorless or near-colorless diamond?

Accepted Answer

Spectroscopic analysis (e.g., UV-Vis or FTIR spectroscopy)

Answer

A standard 10x loupe

Answer

A polariscope set to conoscopic mode

Answer

A refractometer measuring refractive index

Question 7

A customer brings in a diamond ring and mentions the stone looks 'less clear' than when purchased. The jeweler notices a previous repair was done. Which treatment was most likely applied to the original stone?

Accepted Answer

Fracture filling

Answer

HPHT color treatment

Answer

Laser drilling only

Answer

Irradiation for color change