Assignment 17 - Treatments Flashcards
How can laser drilling improve a diamond’s marketability?
Laser drilling can make a diamond more marketable by improving its apprearance.
What are some benefits and disadvantages of fracture filling?
Fracture filling makes the diamond’s fractures and cleavages less visible by using a high-RI glass filler.
What are some disadvantages of fracture filling?
Cleaning or heating can damage the filler, making the diamond less durable.
How can fracture filling be detected?
Some signs of fracture filling are the flash effect, trapped gas bubbles, flow structure, and a crackled texture.
The use of a laser beam to reach a diamond’s dark inclusions and disguise or eliminate them.
Laser drilling
How can color treatments improve a diamond’s marketability?
Less color in colorless diamodns or more attractive colors in colored diamonds increase value.
What methods are used to alter diamond color?
- Irradiation
- Irradiation + Annealing
- HPHT
- LPHT
- Coating
How can you detect irraditation treatments in diamonds?
Strong color concentration round culet, but lab-testing might be required.
What colors do you get by irradiation type I diamonds?
Green to blue
What colors do you get by irradiating type II diamonds?
Blue (sometimes green-blue)
What color do you get by irradiating & annealing type Ia diamonds ?
Yellow, orangey yellow, yellow-green or brown
What color do you get by irradiating & annealing type Ib (strong brown) diamonds ?
pink
How can you detect HPHT treatment?
Graphitization
Formation of graphite around a diamond’s mineral inclusions and feathers that results from the extreme conditions of HPHT treatment
Graphitization
How can you detect coating in diamonds?
Often visible under 10x modification as areas of uncoated spots or scratches.
