PRESIDIUM Synthetic Diamond Screener II Bedienungsanleitung Seite 28

Red Bar of light/Type IIa Diamond
The first light bar on the right will indicate 'Type IIa Diamond' and will
be lit in red (Fig 3.3).
Fig.3.3 'Type IIa' Reading
A 'Type IIa Diamond' reading means the UV light absorption ability
of the tested diamond stone is low and this is due to the lack of trace
elements such as nitrogen within the colorless diamond, allowing the
light to pass through the diamond with little obstruction. The red light
in the 'Type IIa Diamond' reading will alert you that the tested stone
could be a laboratory-grown diamond.
Should you get this result, it is recommended for you to conduct
further testing via other means on this stone as this indicates the
diamond is most likely a laboratory-grown Type IIa diamond or a Type
Ia diamond.
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