Formation of pearl
Pearl (alias genuine pearl) is a substance forming inside shell, and
similar to shell. No matter the natural pearl or artificial cultivated,
pearl is formed when small irritative foreign particle come into shell
by accident, it touches outer membrane, and outer membrane will excrete
a pearl matter to wrap these small particles layer on layer. calcium
carbonate crystal, they are different substances: pearl and shell.
How to choose pearls
In pearls, quality differences can be seen with your own eyes. One
can choose pearls by color, luster, coating, surfacesize, shape and
size.
COLOR
The most common naturally occurring body colors in Akoya cultured
pearls are white, cream and pink. A silver, cream or pink overtone
is considered most desirable in these colors. In black pearls (whether
dyed or natural), including gray and blue hues, blue and green overtones
are considered most desirable
LUSTER
A pearl should have a bright, even, reflective surface. Examine
several strands. How clear is the reflection of your own image in
the su rface of the pearls? The clearer the reflected image, the
higher the luster. High luster is high quality and often (but not
always) indicative of good nacre thickness.
COATING
This refers to the amount of nacre on the nucleus. Most commercial
pearls these day are "thin coat", meaning they were not
left in the oyster long enough. Thin coat pearls are not as lustrous,
and may chip or even peel. To check for thin coat, hold a length
of strand just under a strong light source and roll it back and
forth between your fingers. If you see the "wink" of the
mother-of-pearl (shell) bead through the nacre, the coating is thin.
SURFACE
A pearl with a "clean" surface will reflect light more
evenly and is therefore more valuable than a pearl with a blemished
surface. Most pearls have blemishes, and the smaller and closer
to the drill hole a blemish is, the better. Blemishes on the crest
of a pearls are least desirable.
SHAPE
Round pearls should be just that, round. Even the best strands may
contain the occasional off round bead, however. Pearls are described
as being round, semi-round, off-round, or baroque, in order of descending
desirability (and price). As with color preference, a preference
for round vs. baroque-shaped pearls in a personal thing. Good new
for those who prefer round pearls. you really have to look closely
to notice that they are not absolutely spherical.
SIZE
In strands, pearl sizes are expressed as a size range, 7 x 7.5 mm
means that every pearl in the strand will fall somewhere in that
range. The pearls will generally have been graduated so the ones
closer to 7.5 mm. are in the front. All other factors being equal,
the larger the pearl, the more expensive it will be. Strands 9 x
8.5 mm. or larger will be significantly more expensive. |
