natural material that looks like diamond.
manmade material made primarily of carbon forming in a different crystal system than natural diamond.
manmade material that looks like diamond.
manmade material with essentially the same physical, chemical, and optical properties as natural diamond.
makes up a substantial portion of the market.
is limited to fancy-colored melee, which is mostly synthetic.
is limited by high production costs.
is currently impossible because the synthetics are too highly included.
yellow or brown.
Strong blue under both longwave and shortwave.
Blue under longwave and weak yellow under shortwave.
Strong yellow under longwave and none under shortwave.
Yellow to greenish yellow under both longwave and shortwave.
High-energy electrons in a linear accelerator
only treat diamonds with eye-visible feathers.
don't grade fracture-filled diamonds.
give fracture-filled diamonds grades that are one grade lower than they appear to be.
grade diamonds before they fracture fill them.
D grade colorless
brown , orange and yellow
ammonia in cleaning solutions.
ultraviolet rays in sunlight.
heat during routine repairs.
chlorine in swimming pools.
can be easily determined with standard gemological equipment.
cannot be determined for most diamonds.
should usually be determined by a gemological laboratory.
can be determined using a DiamondSure.
Etched or frosted naturals
Color zoning parallel to facet junctions
don't need to be disclosed to customers.
become permanent clarity characteristics.
aren't permanent, so major labs won't grade them.
usually reduce the clarity grade.
only shallow penetration of the color.
usually green or dark green colors.
distinctive color zoning.
blue or blue-green colors.
has undergone HPHT treatment.
選擇要在Apple App Store上查看的Topgrade應用程序。