The stone is so hard, can it really be engreved?Let's try.

I bought the stones like this:

And the laser engraving machine ,type:BACHIN D8-4035,laser power is 2500mW(output laser power):

The control software is Bachin Draw:

Click on the icon "T",enter the text :BACHIN LASER ,setting the size ,font,Carving Speed set about 1000 to 2000, the laser power is 255(mean 100%).Start engraving!

More:

You can watch the video on YouTube: 

Please leave a message if you have any ideas.Thank you.