Rubies-treatment

Treatment Methods in Rubies

Heat Treatment

The  vast majority of rubies on the market undergo high-temperature heat treatment to enhance their color and clarity. This traditional process is widely accepted in the gemstone industry and is considered a standard practice. Heating intensifies the ruby’s natural red hue and can reduce the visibility of internal inclusions, resulting in a more vibrant and transparent stone.

  • Purpose: To improve color uniformity and enhance clarity

  • Stability: Permanent and stable under normal conditions

  • Disclosure: Reputable dealers always disclose heat treatment, as required by international trade standards

 

Lead Glass-Filling

Some rubies—typically of lower quality—are treated by filling fractures with lead-based glass. This process significantly improves apparent clarity by making internal fractures less visible, often giving the appearance of a much finer ruby. However, glass-filled rubies are not comparable in value to untreated or heat-treated stones.

  • Purpose: To make heavily fractured rubies appear more transparent

  • Stability: Fragile—these stones are highly sensitive to heat, acids, and ultrasonic cleaners, and should be worn and maintained with care

  • Disclosure: This treatment must always be disclosed, as it has a major impact on both price and durability

Other Ruby Treatments

1. Flux Healing

  • What it is: During high-temperature heating, flux (a chemical agent) is added to help heal surface-reaching fractures. The flux melts and fills the cracks, sometimes leaving behind microscopic glassy residues.

  • Purpose: To improve clarity by “healing” fractures.

  • Stability: Generally stable, though less durable than untreated or lightly heated rubies.

  • Disclosure: Must be disclosed; the presence of flux residues can be detected under magnification or via lab testing.

2. Surface Diffusion

  • What it is: A process where coloring agents (usually chromium or other elements) are diffused into the surface of the ruby during heat treatment.

  • Purpose: To enhance or alter the color artificially, especially in pale or less desirable rubies.

  • Stability: Color is only skin-deep; can be lost if the stone is recut or abraded.

  • Disclosure: This is a less accepted and lower-value treatment; must be clearly disclosed.

3. Beryllium Diffusion (rare for rubies)

  • What it is: High-temperature treatment using beryllium to alter the color. This is more common in sapphires but occasionally applied to rubies.

  • Purpose: To create or enhance red-orange hues.

  • Stability: Stable, but the treatment is deep and not always detectable without advanced lab equipment.

  • Disclosure: Considered an advanced, synthetic-style treatment. Should be disclosed.

4. Dyeing (Very Rare and Low-End)

  • What it is: Some very poor-quality ruby composites or porous stones are dyed to enhance color.

  • Purpose: To improve appearance of near-worthless material.

  • Stability: Very unstable; dyes can fade or leach out with cleaning or wear.

  • Disclosure: Should always be disclosed—these are not suitable for fine jewelry.

Treatment Grading and Disclosure

When purchasing emeralds, it’s important to know the extent of any treatment, as it directly affects the gem’s market value and longevity. Reputable laboratories grade treatments as follows:

None: The emerald has not undergone any treatments, making it highly valuable and rare.

Minor: Only a small amount of oil or resin is used to fill fractures. These emeralds are considered high-quality and retain most of their value.

Moderate: A moderate amount of treatment is applied, often visible under magnification. While still beautiful, the emerald’s value is lower than that of untreated or minimally treated stones.

Significant: Extensive treatment has been performed, typically involving larger fractures and more visible treatments. These emeralds are usually more affordable but are considered less desirable by collectors.

In the gemstone trade, transparency about treatments is essential to maintaining trust and accurately reflecting value. Reputable gemological laboratories such as GIA, SSEF, GRS, and AGL assess not only the presence of treatments but also their extent and type, often grading rubies along a spectrum—from untreated, to traditionally heat-treated, to heavily treated (such as glass-filled or diffusion-treated). These distinctions have a significant impact on price and collectibility. For high-value rubies, a laboratory report verifying the treatment status is crucial. Ethical sellers will always provide full disclosure of any treatments and their impact on durability and value, in accordance with international trade standards.