A light and portable instrument that instantly identifies diamonds and most colored gemstones based on their thermal properties.
Presidium Gemstone Tester / Colored Stone Estimator is the only colored gemstone thermal tester in the industry. It provides a quick and easy way to identify diamonds and separate common colored gemstones from one another based on their thermal conductivity. Coated gemstones can also be generally tested with the PGT/CSE.
The Presidium Gem Tester / Colored Stone Estimator has a retractable probe tip that ensures consistent pressure against the gemstone during testing for more reliable results. With the industry’s thinnest probe tip size of 0.6mm, PGT/CSE tests diamonds as small as 0.02ct.
*Does not differentiate between natural and synthetic colored gemstones.
Features
- Retractable thermoelectric probe tip that ensures constant pressure between probe and gemstone
- Industry’s thinnest probe tip (0.6mm) for testing diamonds as small as 0.02ct
- Metal alert buzzer to ensure that probe tip is in contact with gemstone during testing
- Clear and easy-to-read analog dial
- Multi-colored gemstone display
- No waiting time between tests
- Built-in diamond and simulant test discs for reference
- Powered by 2 x AA batteries or adaptor
- Leather carrying case included
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| (Click to Enlarge Image) Built-in test discs |
(Click to Enlarge Image) Easy-to-read analog display |
Dimensions and Weight
- Length: 165mm (6.5 inches)
- Width: 77mm (3.03 inches)
- Height: 77mm (3.03 inches)
- Weight: 260g (without battery)
- Weight: 272g

(Click to Enlarge Image)
Benefits
- Identifies diamonds and most colored gemstones
- Tests both polished and unpolished gemstones
- Tests gemstones as small as 0.02ct
- Consistent and reliable results every time
- No waiting time between tests
- Clear and visible display for ease of reading measurements
- Simple and easy to use
- Light and portable tester that can be used anywhere
Power and Battery
- 5 x AA batteries (approximately 4 hours of continuous use)
- AC adaptor 120 / 230 volts (standard item provided by Presidium)
Measurement Range
- 0.02 carat and above
Operating Conditions
- Operating temperature: 18°C-27°C (65°F-80°F)
- Storage temperature: 10°C- 50°C (50°F-122°F)
Package Contents
- Presidium Gem Tester / Colored Stone Estimator
- Probe pen
- Colored gemstone display
- Built-in test simulant discs
- AC adaptor
- User handbook
- Warranty card
- Leather carrying case
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| (Click to Enlarge Image) Probe pen |
(Click to Enlarge Image) Adaptor |






