Article Search Results

Show Filters
Showing 11 results for "*"
Opal slices before and after water immersion
Hydrophane Opal Treatment

An opal rough is immersed in water and treated with oil and Opticon to observe effects on transparency and play-of-color.

Read More

Fire Opal
Coated Fire Opal in the Chinese Market

An investigation of a coated fire opal recently found in the Chinese market.

Read More

These two opals were represented as natural-color blue and pink opal from Mexico.
Update on Dyed Hydrophane Opal

Opal purportedly from a new deposit is found to be dyed.

Read More

Summer 2016 Gems & Gemology Cover
Article
Summer 2016 G&G: Diamonds from Diavik, Responsible Sourcing, and Fabergé Cossack Figures

A summary of the content found in the Summer 2016 issue of Gems & Gemology.

Read More

Treated Andamooka Matrix Opal
Treated Andamooka Matrix Opal

Matrix opal from Andamooka, in South Australia, is a precious opal-included porous rock that is commonly color enhanced (carbon impregnated) to imitate the highly prized black opal from Lightning Ridge in northern New South Wales, Australia.

Read More

Abstracts; Winter 1991

This article, from the Winter 1991 issue of Gems & Gemology, is a compilation of abstracts of important gemology-related articles published outside of Gems & Gemology.

Read More

Abstract Header from the 2009 issue of Gems & Gemology
Abstracts; Winter 2009

This article, from the Winter 2009 issue of Gems & Gemology, is a compilation of abstracts of important gemology-related articles published outside of Gems & Gemology.

Read More

Milky white opals
UV-Reactive Opal

The first documented UV-reactive chemical treatment to make opal appear tenebrescent.

Read More

Abstract Header from the 2009 issue of Gems & Gemology
Abstracts; Summer 2009

This article, from the Summer 2009 issue of Gems & Gemology, is a compilation of abstracts of important gemology-related articles published outside of Gems & Gemology.

Read More

A Useful Technique to Confirm the Hydrophane Nature of Opal

Observing a water drop’s interaction with opal, as well as refractive index, can confirm a specimen’s hydrophane nature with less risk of breakage than total immersion.

Read More