We recommend adding the Filter 4 which will help you distinguish between a natural fluorescing diamond and a lab created one.
GemPen® Diamond Screener is used to screen diamonds for HPHT and CVD synthetics and includes Filter 1. It also gives indications on treatments such as HPHT treatment. It is possible to later upgrade your GemPen® Diamond Screener by buying the additional Filter Kit.
Available on backorder