Assignment 2 Flashcards
Crossing of chatoyant bands, creating a star in the dome of a cabochon
Asterism
The cloudy bluish white light in the moonstone, caused by scattering of light
Adularescence
A glittery effect caused by light reflecting from small, flat inclusions within a gemstone
Aventurescence
A gemstone’s basic color, determined by its selective absorption of light
Bodycolor
Bands of light in certain gems, caused by reflection of light from many parallel, needle- like inclusions or hollow tubes
Chatoyancy
Small defect in the atomic structure of a material that can absorb light and give rise to a color
Color center
A distinct change in gem color under different type of lighting
Color change
The selection of color in which a gemstone occurs
Color range
Areas of different color in a gem, caused by variations in growth conditions
Color zoning
The separation of white light into spectral colors
Dispersion
Dark areas in the faceted transparent colored stone
Extinction
The color or colors in a gemstone’s color range considered by the trade to the most desirable
Fine color
Emission of visible light by a material when it is simulated by ultraviolet radiation
Florescence
The first impression of an object’s basic color
Hue
A rainbow effect created when light is broken up into spectral hues by thin layers
Iridescence
A broad flash of color in labradorite feldspar that disappears when the gem is moved
Labradorescence
A two-toned effect seen when a chatoyant gem is positioned at right angles to a light source
Milk and honey
Iridescence seen in some natural and cultured pearls and mother of pearl
Orient
The flashing rainbow colors in Opal
Play of color
When a gem shows different bodycolors from different directions
Pleochroism
The color’s strength of intensity
Saturation
Process by which a material absorbs some components of visible light and returns others
Selective absorption
Degree of darkness or lightness of a color
Tone
Terms often used in the jewelry industry to describe particular gemstone colors or link gems with specific geographic locations
Trade terms
An area of weak saturation in a transparent gemstone’s bodycolor that usually results from the way the gem was cut
Window
