Unexpected Inclusions with
Anthony de Goutière
Anthony de Goutière shows us the unexpected beauty that can be found in the
fractures, gas bubbles, and cleavage planes of gemstone inclusions.
Inclusions are irregularities that are found within many gemstones. They are an important diagnostic tool and can occur in the form of liquids, gas bubbles, minerals and combinations of these substances. They provide gemmologists with vital clues in identifying gems and can also help determine the origins of some species.
Beginning his career as a watchmaker and continuing it as a Graduate Gemmologist, Anthony de Goutière has been photographing these tiny phenomena with the eye of an artist and the hand of a craftsman for over 30 years. Through a variety of photomicrographic techniques, he has documented cleavage planes, surface inclusions, and fracture surfaces in wonderfully unusual and artistic scenes. Anthony hopes to inspire other gemologists to search for and document the elusive beauty of gemstone inclusions.
↥ Topaz crystal specimen from Brazil
I found this specimen at a gem show in Tucson, Arizona. The brown rock-looking feature is actually a fractured surface on the back of the specimen. The strings of bubbles are minute hexagonal crystals that have formed in a parting plane or fissure. The smoothness of the seabed-like features and the bubbles seemingly rising to the surface remind me of a scene of kelp swaying underwater.
↥ Light blue sapphire specimen from Sri Lanka
This specimen displays remains of a liquid inclusion and has reddish rutile crystals scattered throughout. This inclusion cluster was almost invisible until I held the specimen between a pair of polarizing filters over the built-in light of the microscope. Rotating the filters creates interference colours and growth features that can be as attractive as they are diagnostic.
↥ Facetted colour-change Zultanite from Turkey
Zultanite is actually a relative newcomer to the gem industry. Discovered as early as 1801 in the Ural Mountains of Russia, it has only recently been commercially mined. It has the amazing quality of being able to change colour under different lighting conditions.
Under natural or fluorescent light, Zultanite has a kiwi green color, with flashes of yellow. Under incandescent lighting, this shifts to a champagne color, and when exposed to subdued lighting, such as candlelight, Zultanite has a pinkish color. The larger the stone, the more pronounced the color change effect.
↥ Colourless beryl crystal specimen
This specimen features unusual growth formations found at the base of a deep natural cavity. I purchased this specimen at a gem show because of its unusual tabular shape and only recently discovered these scenes in cavities on the surface of the specimen. Upon investigation, the surface cavities appeared as a kind of extra-terrestrial environment.
↥ Colourless topaz specimen
This surface fracture on a colourless topaz specimen revealed an assortment of shapes and interference colours. I utilize a variety of lighting techniques to discover unexpected layers, crevices, inclusions within a gemstone. For this specimen, I used several fibre-optic pin-point illuminators and found this wonderful scene.
↥ One of many intricate muscovite (mica) inclusions in a large facetted aquamarine from Brazil
The use of polarizing filters creates the interference colours shown in these inclusions. Muscovite is an interesting mineral that in larger proportions readily cleaves into thin transparent sheets. The ability of muscovite to split into thin transparent sheets – sometimes several feet across – gave it an early use as window panes in 18th century Russia.
↥ Decrepitation halo in a peridot specimen from Arizona.
A decrepitation halo occurs when a liquid inclusion within a gem is heated and exerts pressure within the specimen. This often occurs in peridot specimens and can leave lily-pad like inculsions.
Peridot is a well-known and ancient gemstone, with pieces dating all the Pharaohs in Egypt. While the gem itself is generally a light or olive green colour, decrepitated inclusions can appear dark with several sharply pointed corners when viewed under a microscope.