Transcontinental Tool Co


The industry’s most trusted colored gemstone tester is now redesigned to be more compact, sturdy and portable.

In it’s second generation, the Presidium Gem Tester II provides a quick and easy way to identify diamonds/moissanites and separates up to 16 common colored gemstones based on their thermal conductivity with its clear and direct analog display. A newly redesigned inbuilt calibration reference and adjustment provides ease of operation both indoors and outdoors.

The Presidium Gem Tester II features the industry’s thinnest retractable probe tip (0.6mm) for testing colored gemstones as small as 0.02 carats. Coated gemstones can also be generally tested with PGT II.

*Does not differentiate between natural and synthetic colored gemstones.


  • Retractable thermoelectric probe tip that ensures constant pressure between probe and gemstone
  • Industry’s thinnest probe tip (0.6mm) for testing gemstones as small as 0.02 carats
  • Metal alert buzzer to ensure probe tip is in contact with gemstone during testing
  • Clear and easy-to-read analog dial
  • Can differentiate between 16 types of gemstones
  • Built-in Glass and Calibration (CAL) test discs for reference


  • Identifies diamonds/moissanites and most common colored gemstones
  • Tests both polished and unpolished gemstones
  • Tests gemstones as small as 0.02 carats
  • Consistent and reliable results every time
  • No waiting time between tests
  • Simple and easy to use
  • Runs on 2 AA batteries or adaptor (included)