PRESIDIUM DC709N, User Handbook Manual, Page: 19 / 138

Sapphire vs. Tanzanite Jadeite vs. Chrysoprase
Sapphire vs. Iolite Jadeite vs. Aventurine
Quartz
Sapphire vs. Spinel Ruby vs. Spinel
Sapphire vs. Citrine Ruby vs. Garnet
Sapphire vs. Topaz Topaz vs. Aquamarine
Sapphire vs. Tourmaline Topaz vs. Amethyst
Emerald vs. Jadeite Topaz vs. Citrine
Emerald vs. Garnet Spinel vs. Garnet
Jadeite vs. Garnet Gemstones vs. Glass
The use of the thermal results is restricted to the
gemstones listed above and will assist the jeweler to
distinguish the many confusing gemstones in the market.
Reading optical test results
• A Reflectivity Number is displayed. Note the Reflectivity
Number and compare it with the reflectivity chart at
tached in the package.
• In case of a borderline reading, clean the stone and
pad again before the next test and/or move stone
slightly off center. By repositioning the stone, a dis
torted reflection from a scratched area of the surface
may be avoided. Repeat the test.
• Synthetic Spinel/Synthetic Sapphire and High Zircon/
GGG have overlapping Reflectivity Numbers. If in
doubt, use thermal conductivity measurement for easy
separation.
• Synthetic Sapphire: needle goes to a high position in
the red zone.
• Synthetic Spinel: Needle goes about halfway into the
red zone.
• High Zircon: Needle goes 2/3 into the red zone.
• GGG: Needle goes 1/3 into the red zone
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