PRESIDIUM Refractive Index Meter II User Manual

The test results are indicated as follows:
• A Refractive Index Reference List is provided for
easy reference to end-user. This list comprises
common gemstones available in the market. The
gemstones are arranged according to descending
Refractive Index. Please refer to attached table.
• The list includes the range of refractive index of
gemstones with respective tolerance provided in
brackets.
• The tolerance in refractive index is due to the
tolerance from the photo-sensor used.
• Example: The refractive index for sapphire is 1.757
(-0.016) – 1.790. The reading in bracket refers to the
tolerance. In other words, the R.I. reading of sapphire
from the unit ranges from 1.741 – 1.790.
• 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
distorted reection from a scratched area of the
surface may be avoided. Repeat the test.
3. READING TEST RESULTS with your Presidium
Refractive Index Meter II
16

PRESIDIUM Refractive Index Meter II Specifications

General

Brand	PRESIDIUM
Model	Refractive Index Meter II
Category	Measuring Instruments
Language	English