Phenomenon

Color change phenomenon is also depends on the thickness of the stone with the light. More color change is visible with the thicker stone.

Phenomenon
An optical effect which appears in certain gemstone materials. Often revealed by or enhanced by proper fashioning.
Phosphorescence
A continuing glow exhibited by some gemstones after the source of illumination has been removed.

Optical Phenomenon: Orient, in fine specimens All text and images, unless otherwise designated, © 2008 Barbara Smigel ...

The phenomenon of magnetism is "mediated" by the magnetic field -- i.e., an electric current or magnetic dipole creates a magnetic field, and that field, in turn, imparts magnetic forces on other particles that are in the fields.

The phenomenon that occurs when diamonds are exposed to UV light causing them to fluoresce with visible light.
Luster ...

The phenomenon in which each ray of light is split in tow as it enters a noncubic mineral. Each ray travels at different speeds and has its own refractive index.
Doublet
Composite stone made of two pieces cemented or glued together.

This phenomenon can be observed in everything from the "thin film" interference of a soap bubble, to seashell nacre, oil slicks, butterfly wings, and minerals such as ammolite, cat's eye, feldspar, labradorite and opal.

A recent phenomenon, virtually unheard of before the early 1980s, is the publication of periodicals produced by the supporters themselves.

CHATOYANCY A phenomenon caused by reflections from parallel needle like inclusions in a cabochon such as cat's-eye gemstone. Chatoyancy can be seen in some flat gemstones but a cabochon cut enhances the effect.

An eye catching phenomenon of fluorite is its distinctive multicolored banding. Chunky fluorite bead strands optimize this exceptional effect.

CHATOYANCY - The phenomenon of a sharp, well defined band or streak of light across the dome of a gem material caused by the reflection of light from parallel needle-like inclusions.

Dispersion is the phenomenon which is caused by the separation of a white light into spectral colors of different hues.

The floating light phenomenon and sheen within these gemstones is called Adularescence or Schiller.

Asterism:An optical phenomenon displayed by certain gemstones such as rubies or sapphires that reflects the shape of a star on the surface of a cabochon cut from the stone. The stars may have four, six, or twelve rays.

Alexandrite EffectThe "Alexandrite Effect" is a phenomenon in which a stone appears to be different colors depending upon the type of light it is viewed in.

Alexandrite EffectA phenomenon in which a stone appears to be different colors in different types of light . AlexandriteA form of the mineral chrysoberyl noted for its color change in different forms of light.

A natural phenomenon that has been proven to occur invariably whenever certain conditions are met. 2. A formal statement describing such a phenomenon and the conditions under which it occurs. Also called law.

But of equal importance is that jade connoisseurship is almost strictly a Chinese phenomenon.

The floating-light phenomenon and sheen of moonstone are called adularescence or schiller. The light is scattered by alternating layers of two kinds of feldspar and produces a misty luster of white, dull yellow, yellow-gray or greenish-gray.

Labradorescence: Labradorescence is a phenomenon. It is the shimmer of color that appears to wash over a labradorite gemstone's surface. The color changes as the light source moves.

This phenomenon is caused by very fine needles of rutile. And now and then one of the rare star rubies is found.

Star Sapphires are classified as "phenomenon" stones, as it wasn't always known how the six-rayed star was created within these sapphires.

This phenomenon occurs due to an internal diffraction of light which disperses a spectrum of iridescent colors.

Modern cutters make use of an optical phenomenon named total internal reflection to let as much light as possible, that enters the stone, to be redirected back to the eye.

This is a natural phenomenon caused by trace elements present when the diamond crystal was formed. Some of the most prized and rare colors are true red, purple, and green.

Some Diamonds (1 out of 10) have a natural phenomenon called Fluorescence. Fluorescence is where a Diamond will actually Glow in the Dark under an Ultraviolet light (think Black Light). Some will Glow Blue, some Yellow, some Red.

This phenomenon has a scientific explanation that the green color is generally the outcome of the crystals colliding with a radioactive supply at several positions during its life span and from geological point of view this life span is measured in ...

Star sapphire: Also known as "phenomenon stones", star sapphires are created by an illusion of light.

LIGHTING : A great deal of Tanzanite marketing makes a big deal of the "red flash" phenomenon of Tanzanite. This is one of the features of the stone and is due to Tanzanite's trichroism.

The phenomenon is caused by fibrous or needle-like inclusions that interfere with the passage of light. As the light is scattered, a portion is reflected back to the viewer.

The freeze-thaw cycle is phenomenon in cold areas in which water that is trapped in rock cracks (and between rocks) alternately freezes in the winter and thaws in the summer (or even alternately freezes and thaws during the day and the night).

Colorless to yellowish gray, highly translucent to semitransparent variety of Feldspar that reflects light in a distinctive shimmering phenomenon known as adularescence.

CHANGE OF COLOR (COLOR CHANGE) - A phenomenon of some colored stones in which the gem material appears a different color in different types of light.

Aurora Borealis A rainbow-like iridescent finish that is reminiscent of the weather phenomenon called Aurora Borealis, or the Northern Lights.

Cats Eye - Chatoyancy is a phenomenon seen in various gems when they are cabochon cut, resulting in a bright single line down the center.
Ceylon Sapphire - These deep royal blue sapphires from Sri Lanka, formally Ceylon, are the finest in the world.

Double Refraction
This is the term for the phenomenon where each ray of visible light is split into two as it enters a noncubic mineral. Each light ray in the spectrum travels at different speeds and has its own refractive index ...

Fluoresence - Fluorescence, a fascinating natural phenomenon, is the tendency of some gemstones to reflect a distinct color when exposed to ultraviolet light.
Fluted - This design motif features rounded grooves in the surface of the piece.

ADULARESCENCE: An optical phenomenon applied to orthoclase or adulria feldspar that exhibits a floating, billowy, white or bluish light effect.

Transformation, despite the implication that it's an overnight phenomenon, is best accomplished slowly, and a member of the jasper family is ideal for this purposeÑspecifically, the multi-patterned Picasso jasper.

The hearts and arrows phenomenon quickly spread from Japan to the U.S in the early 1990s.

Cats-Eye Chrysoberyl - Display Chatoyancy which is a phenomenon seen in various gems when they are cabochon cut, resulting in a bright single line down the center.

If a fluorescent material continues to emit light after the exciting UV or X-ray light is removed, it is said to be phosphorescent. This phenomenon usually lasts only a few seconds but may occasionally persist for much longer periods.

Some Thai rubies have black reflections, a phenomenon called extinction, which can make their color look darker than it really is. But Thai rubies can also have a rich vivid red that rivals the Burmese in intensity.

Inclusions are an accepted natural phenomenon and do not always affect the desirability of the gemstone. It is standard gemstone industry practice to enhance gemstones to improve their natural qualities.

This phenomenon of fluorescence and/or phosphorescence is the result of UV radiation absorbed by impurities or structural defects within the crystal structure, resulting in an oscillation of electrons between energy levels, ...

Phenomena: Special properties exhibited by certain gemstones. An excellent example of a phenomenon is the color-change property of the alexandrite.

The variety of chrysoberyl containing rutile needles or negative crystals oriented in the same direction showing some exceptional and sharp chatoyancy is called cat's eye. This optical phenomenon produces the appearance of the likeness of a cat's ...

These magnificent gems display a sharp six-rayed star which seems to glide and shimmer magically across the surface of the gem when the latter is moved. This is caused due to an optical phenomenon known as "Asterism".

Europe, Japan and North America had experienced a similar phenomenon) decades before. Much mischief was made (in those countries), but me technology more closely matched the minds of the countries) as a whole." ...

Diamond is highly resistant to wetting by water. We will attempt to add a scientific explanation of this phenomenon at a later date.
WFDB, W.F.D.B., World Federation of Diamond Bourses
See our Bourse page.

Very fine, high quality rubies can be worth even more than diamonds. Ruby is in the corundum species. Star rubies also exhibit a star-like phenomenon, known as asterism. Rubies are found all over the world with the finest rubies are Burmese.

The phenomenon called color is thus a description of the differentiation by the eye between various wavelengths and combinations of wavelengths of visible light.

Sapphire is most commonly found in and around Sri Lanka and Burma, and the highest quality sapphire gemstones are mined there. The star in a star sapphire is the result of the inclusion of rutile in the stone, a phenomenon rarely found in the ...

When interacting with light, similarly oriented, miniscule inclusions of copper or hematite platelets exhibit glittering, spangled reflections, shimmering through different depths within the gem
Some experts refer to this phenomenon as ...

In natural light, colour-change Sapphire is blue, but in artificial light, it is violet. (This effect is the same phenomenon well-known in the gemstone Alexandrite).

In the first attempts at a definition of the color; however, it was realized that the color stage Jager did not represent a slight blue suffusion, but that the visible bluish coloration present was caused by another phenomenon: by fluorescence.

In such cases, the beauty of this unique phenomenon makes up for some loss of crystal. Although Kashmir sapphires can hardly be described as limpid, the best still retain a moderate degree of transparency.
139. Tagore, Mani Mala, vol. 1, pp.

When a light is shined on the stone, one side of the stone is the color of milk and the other is the color of honey. When the light changes direction, the color effect also shifts. Cat's-eye chrysoberyl can exhibit this milk and honey phenomenon.

Double Refraction - An optical phenomenon of some minerals which splits rays of light into two rays.
Double-Terminated - A crystal displaying termination faces on both ends.

Spessartite garnet can be red, reddish orange, orange, yellow-brown, reddish brown, or blackish brown. A few garnets exhibit a color-change phenomenon.

See also: Stone, Color, Gemstone, Rough, Crystal