الوصف

Chelsea filter is color disc only allow the light of deep red and Kelly to get through, it makes the color of colored gem change. Chelsea filter has a wide use in testing gem, it can distinguish the regents which color on the gem, and detects coloration, compare different kinds of jade according to the color change when use the Chelsea filter，it can tell jade from the other gem. Chelsea filter FCF*2 adopt excellent spectral color filter. it has a better effect, never fade, it can also tell ruby from other red gem.

Chelsea filter is easy to use, but also need to pay attention to the follow points.

1. Requirement of source

  You can use different source to strengthen the effect when testing different kind of gem.

â‘  Useelectric incandescent lamp as a light source to test the green and blue gem, you will get the best effect. When there is no electric incandescent, can test directly under the daylight lamp, but the color will be different from the one under electric incandescent, pls pay attention to this.

â‘¡to red gem, you will get the best effect use the daylight lamp or sunlight

â‘¢Make the sample close to the light source to get enough light, and avoid the disturb of other lights.

2. Way of observe: make your eyes close to the Chelsea filter, and ****0cm to the sample