How to verify a jade certificate

Most of my jade come form Zhong Gong Germ Testing Centre. It is a national lab in China.

I use one regular bangle in my store and the certificate from Zhong Gong Germ Testing Centre as an example. 

This one:

Here is the certifcate:

Front

 Back:

There are two way to verify it.

1, scan the code.

Here is the QR code:

Open the built-in camera app while your phone connected to wifi. Point the camera at the QR code. Tap the banner that appears on your phone.

This will bring you to the website of the certificate. 

 https://www.zbtesting.com/Api?u=dw.m.P2311008375

 2. Check it on the website.

Go to the website on the back of the certifcate.

http://www.gtc168.com

Put the number on certifcate for the checking. It will show the checking result.