Ass 17 - Diamond Treatments Overview

A diamond that has been exposed to radiation from a cyclotron, resulting in color zoning patterns.

The time it takes for half of the radioactive atoms in a substance to decay.

A device used to detect and measure radioactivity.

Radiation displaces carbon atoms creating vacancies in the crystal structure, absorbing red light and transmitting blue/green, causing a blue/green color.

Nitrogen atoms replace carbon atoms, leading to blue or yellow coloration in diamonds based on nitrogen arrangement.

Diamonds with negligible nitrogen impurities resulting in a pure blue color after irradiation. (Most often type IIa).

A process of controlled heating and cooling to modify a diamond's color, by causing vacancies and impurities to rearrange.

A specific defect created when type IIa diamonds are irradiated similar to that observed in type I diamonds.

Irradiation and annealing of diamonds can create various colors, like yellow, orange-yellow, yellow-green, or brown, from blue-green diamonds.

Type Ia diamonds are a mix of IaA and IaB types, which when irradiated and annealed create H3 and H4 defects.

Type Ib diamonds, rare in nature, are often treated to produce a specific color, usually pink, depending on the starting brown color and irradiation duration.

Identifying irradiation treatments in diamonds is challenging, but advanced labs use specialized equipment to determine its origin.

Treated diamonds may exhibit concentrated color around the culet (bottom) or on surface facets.

Determining if a green diamond is natural or artificially treated can be very complex, even with the best technology.

Scientists use this process to alter a diamond's color by moving and rearranging defects within its crystal structure.

HPHT treatment causes noticeable surface etching and pitting, requiring repolishing afterwards.

A famous diamond, treated multiple times, has a recorded history through different owners and treatments dating far back.

Heat is usually unlikely to change the color of most irradiation-annealing color treatments

A rapid change in color observed when a fractured diamond is viewed under a gemological microscope, indicating the presence of fracture-filling materials.

The process of filling cracks or fractures in a diamond with materials to improve its appearance, often using glass or resin.

A technique used in gemological microscopes where light is directed from the sides, highlighting surface features and revealing subtle color changes.

A gemological lighting technique using direct illumination from above, highlighting interior features and revealing internal colors.

Modifying the color of a diamond through various processes to enhance its attractiveness or achieve desirable hues.

Exposing diamonds to high-energy radiation to create or enhance their color.

A machine used in irradiation treatment to accelerate atomic particles along a straight path, bombarding diamonds with high-energy electrons.

A device that accelerates atomic particles along a circular path, used for nuclear research and irradiation treatments.

A treatment that permanently alters the diamond's color, meaning it cannot be reversed to its original state.

Irradiation can create uneven color distribution within a diamond, resulting in distinct color zones.

A high-pressure, high-temperature process used to change the color of diamonds by rearranging their crystal structure. This involves moving existing vacancies and nitrogen atoms within the diamond.

Diamonds containing nitrogen impurities, which can be manipulated by HPHT treatment to create various bodycolors, like yellow, orange, or green.

Diamonds with almost no nitrogen impurities. HPHT treatment can remove brown color, but does not create new bodycolors.

A process where carbon atoms in a diamond rearrange into a graphite structure, often seen as a sign of HPHT treatment.

A process using a combination of HPHT, irradiation, and annealing to achieve a desired bodycolor in a diamond.

A lower-pressure, high-temperature process similar to HPHT, but primarily used to create black color by inducing graphitization in surface fractures of diamonds.

Diamonds that have been coated with various materials, such as fluorides and silica, to alter their color.

The process of altering the natural color of a diamond using various treatments, including HPHT, irradiation, annealing, and coating.

Advanced techniques such as photoluminescence spectroscopy are used to detect HPHT treatments. Additionally, signs like graphitization around inclusions and etched or frosted naturals can indicate treatment.

A treatment that uses a laser to create a tiny tunnel in a diamond, allowing for acid to bleach or etch out inclusions, or for the laser to vaporize them.

A treatment that uses a laser to heat an inclusion near the surface, causing cleavages to expand and form channels for acid or bleach to lighten the inclusion.

Laser drilling creates permanent changes in the diamond, visible under magnification as tiny feathers or channels with a sugary or frosted appearance.

Fracture filling can slightly lower a diamond's color grade and can be damaged by common jewelry repair procedures.