Diamonds And Color (Chapter 12, Key Terms & Key Concepts) Flashcards
Annealing—Using heat to stabilize irradiated color in
gemstones.
Annealing
Structural defect that influences an
object’s absorption of light and can cause its color.
Color center
Yellow, brown, and gray diamonds
with more color than the Z masterstone, or that
exhibit any other color face-up.
Colored diamonds
Emission of visible light by a material
when it’s exposed to ultraviolet radiation
Fluorescence
Range of diamond colors from
colorless to light yellow, brown, and gray, also called
the D-to-Z range.
Normal color range
Process by which a material
absorbs some wavelengths of light and transmits
others.
Selective absorption
Many people think of diamonds as colorless, but most diamonds
have a small amount of color, usually yellow or brown.
Key Concept
The three elements used to describe color are hue, tone, and
saturation.
Key Concept
The presence of impurities and structural defects are two
common causes of color in diamonds
Key Concept
Nitrogen is the most common impurity element in diamond
and the most common cause of its yellow color.
Key Concept
About 35 percent of gem-quality diamonds fluoresce when
they’re exposed to ultraviolet radiation, and most of them
fluoresce blue.
Key Concept
Ethical gem professionals disclose all diamond treatments
Key Concept
Colored diamonds are far more rare than diamonds in the
normal color range.
Key Concept
With colored diamonds, value depends on the amount of color
they possess
Key Concept
Brown is the most common colored diamond color.
Key Concept
Increased supply and marketing led to the growing popularity
of colored diamonds.
Key Concept
The relative lightness or darkness of a color is called its
tone.
The emission of visible light by a material when it’s exposed to ultraviolet radiation is called
fluorescence.
The most common colored diamond color is
brown.
Which of the following diamond colors would be the most valuable, all other factors being equal?
Red
Type IIb diamonds contain
boron.
When boron is present in a diamond’s crystal structure, it colors the diamond
blue.
A common method of permanently changing the color of a diamond is
irradiating.
The basic causes of a diamond’s color are its crystal structure and
chemical composition.
Diamonds that are colorless to light yellow, brown, and gray fall into the
normal color range.
Type I diamonds contain
nitrogen.
When a gem absorbs some wavelengths of light and transmits others, the process is called
color center
The most common impurity element found in diamond is
nitrogen.
The most commonly observed color of fluorescence in gem diamond is
blue.
A structural defect that influences a gem’s absorption of light is called a(n)
selective absorption
A noticeable “oily” appearance seen in some diamonds is usually the result of
very strong fluorescence
