How to distinguish the true from the false? Identify all kinds of diamonds under purple light

I think it is a very effective way to identify amber with violet lamp, but there is no unified reference standard because of the different sources of violet lamp in the market. How to identify the true and false of this purple light diamond? Next, I'll teach you to identify all kinds of amber under the purple light.

how to distinguish the true from the false when the diamond is illuminated by purple light? Oil test: use a special oil-based ink pen or ball point pen to draw a line on the diamond table, which will leave an uninterrupted straight line. Other imitations are not lipophilic, leaving intermittent dots and lines at the line.

Water drop test: the water drops on the diamond will remain spherical for a long time, while the water drops on the imitation will disperse in a relatively short time.

Breath test: breath on the diamond. If the moisture on the diamond disappears immediately, it is a real diamond. If the moisture stays on the diamond for a few seconds, it is a fake diamond.

Feeling test: when touching diamonds and their imitations with your tongue at room temperature, diamonds are much cooler than imitations.